CWE-22
Weakness Allowed-with-ReviewImproper Limitation of a Pathname to a Restricted Directory
Abstraction: Base · Status: Stable
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
Many file operations are intended to take place within a restricted directory. By using special elements such as ".." and "/" separators, attackers can escape outside of the restricted location to access files or directories that are elsewhere on the system. One of the most common special elements is the "../" sequence, which in most modern operating systems is interpreted as the parent directory of the current location. This is referred to as relative path traversal. Path traversal also covers the use of absolute pathnames such as "/usr/local/bin" to access unexpected files. This is referred to as absolute path traversal.
Mapping guidance
This CWE entry might have children that would be more appropriate.
Examine children of this entry to see if there is a better fit. Consider children such as CWE-23 (or its descendants) for relative path traversal, or CWE-36 for absolute path traversal.
Relationships and members
Modes of introduction
Detection methods
Automated Static Analysis
Automated techniques can find areas where path traversal weaknesses exist. However, tuning or customization may be required to remove or de-prioritize path-traversal problems that are only exploitable by the product's administrator - or other privileged users - and thus potentially valid behavior or, at worst, a bug instead of a vulnerability.
Effectiveness: High
Manual Static Analysis
Manual white box techniques may be able to provide sufficient code coverage and reduction of false positives if all file access operations can be assessed within limited time constraints.
Effectiveness: High
Automated Static Analysis - Binary or Bytecode
According to SOAR [REF-1479], the following detection techniques may be useful:
Highly cost effective:
Bytecode Weakness Analysis - including disassembler + source code weakness analysis
Cost effective for partial coverage:
Binary Weakness Analysis - including disassembler + source code weakness analysis
Effectiveness: High
Manual Static Analysis - Binary or Bytecode
According to SOAR [REF-1479], the following detection techniques may be useful:
Cost effective for partial coverage:
Binary / Bytecode disassembler - then use manual analysis for vulnerabilities & anomalies
Effectiveness: SOAR Partial
Dynamic Analysis with Automated Results Interpretation
According to SOAR [REF-1479], the following detection techniques may be useful:
Highly cost effective:
Web Application Scanner
Web Services Scanner
Database Scanners
Effectiveness: High
Dynamic Analysis with Manual Results Interpretation
According to SOAR [REF-1479], the following detection techniques may be useful:
Highly cost effective:
Fuzz Tester
Framework-based Fuzzer
Effectiveness: High
Manual Static Analysis - Source Code
According to SOAR [REF-1479], the following detection techniques may be useful:
Highly cost effective:
Manual Source Code Review (not inspections)
Cost effective for partial coverage:
Focused Manual Spotcheck - Focused manual analysis of source
Effectiveness: High
Automated Static Analysis - Source Code
According to SOAR [REF-1479], the following detection techniques may be useful:
Highly cost effective:
Source code Weakness Analyzer
Context-configured Source Code Weakness Analyzer
Effectiveness: High
Architecture or Design Review
According to SOAR [REF-1479], the following detection techniques may be useful:
Highly cost effective:
Formal Methods / Correct-By-Construction
Cost effective for partial coverage:
Inspection (IEEE 1028 standard) (can apply to requirements, design, source code, etc.)
Effectiveness: High
Notes
Other
In many programming languages, the injection of a null byte (the 0 or NUL) may allow an attacker to truncate a generated filename to apply to a wider range of files. For example, the product may add ".txt" to any pathname, thus limiting the attacker to text files, but a null injection may effectively remove this restriction.
Relationship
Pathname equivalence can be regarded as a type of canonicalization error.
Relationship
Some pathname equivalence issues are not directly related to directory traversal, rather are used to bypass security-relevant checks for whether a file/directory can be accessed by the attacker (e.g. a trailing "/" on a filename could bypass access rules that don't expect a trailing /, causing a server to provide the file when it normally would not).
Terminology
Like other weaknesses, terminology is often based on the types of manipulations used, instead of the underlying weaknesses. Some people use "directory traversal" only to refer to the injection of ".." and equivalent sequences whose specific meaning is to traverse directories.
Other variants like "absolute pathname" and "drive letter" have the *effect* of directory traversal, but some people may not call it such, since it doesn't involve ".." or equivalent.
Research Gap
Many variants of path traversal attacks are probably under-studied with respect to root cause. CWE-790 and CWE-182 begin to cover part of this gap.
Research Gap
Incomplete diagnosis or reporting of vulnerabilities can make it difficult to know which variant is affected. For example, a researcher might say that "..\" is vulnerable, but not test "../" which may also be vulnerable.
Any combination of directory separators ("/", "\", etc.) and numbers of "." (e.g. "....") can produce unique variants; for example, the "//../" variant is not listed (CVE-2004-0325). See this entry's children and lower-level descendants.
Content history
Identified weakness in Perl demonstrative example
Provided diagram to improve CWE usability
Identified weakness in "good code" for Python demonstrative example
Provided a demonstrative example in PHP
updated Potential_Mitigations, Time_of_Introduction
Suggested OWASP Top Ten 2004 mapping
updated Alternate_Terms, Relationships, Other_Notes, Relationship_Notes, Relevant_Properties, Taxonomy_Mappings, Weakness_Ordinalities
updated Description
updated Relationships, Taxonomy_Mappings
updated Potential_Mitigations
updated Alternate_Terms, Applicable_Platforms, Common_Consequences, Demonstrative_Examples, Description, Detection_Factors, Likelihood_of_Exploit, Name, Observed_Examples, Other_Notes, Potential_Mitigations, References, Related_Attack_Patterns, Relationship_Notes, Relationships, Research_Gaps, Taxonomy_Mappings, Terminology_Notes, Time_of_Introduction, Weakness_Ordinalities
updated Common_Consequences, Demonstrative_Examples, Description, Detection_Factors, Potential_Mitigations, References, Relationships
updated Potential_Mitigations
updated Potential_Mitigations
updated Potential_Mitigations
updated Relationships
updated Potential_Mitigations, References, Relationships, Taxonomy_Mappings
updated Demonstrative_Examples, References, Relationships
updated Potential_Mitigations
updated Observed_Examples
updated Related_Attack_Patterns, Relationships
updated Other_Notes, Research_Gaps
updated Detection_Factors, Relationships, Taxonomy_Mappings
updated Relationships
updated Related_Attack_Patterns
updated Demonstrative_Examples
updated Affected_Resources, Causal_Nature, Likelihood_of_Exploit, References, Relationships, Relevant_Properties, Taxonomy_Mappings
updated References, Relationships
updated References, Related_Attack_Patterns, Relationships, Taxonomy_Mappings
updated Related_Attack_Patterns, Relationships, Type
updated Relationships
updated Potential_Mitigations, Relationships
updated Demonstrative_Examples, Potential_Mitigations
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updated Potential_Mitigations, Relationships
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updated Observed_Examples, Relationships
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updated Common_Consequences, Description, Detection_Factors
updated Demonstrative_Examples, References, Relationships, Time_of_Introduction
updated Mapping_Notes, Relationships
updated Observed_Examples
updated Common_Consequences, Description, Diagram, Observed_Examples, Other_Notes, References
updated Demonstrative_Examples, Relationships
updated Relationships
updated Applicable_Platforms, Detection_Factors, Observed_Examples, Potential_Mitigations, References
updated Mapping_Notes, Relationships
updated Alternate_Terms, Applicable_Platforms, Demonstrative_Examples, Relationships
updated Applicable_Platforms, Common_Consequences, Name, References, Relationships, Taxonomy_Mappings
16162 vulnerabilities reference this CWE, most recent first.
GHSA-625Q-87RR-W32G
Vulnerability from github – Published: 2022-07-12 00:00 – Updated: 2022-07-16 00:00The DSAB-local/DSAB repository through 2019-02-18 on GitHub allows absolute path traversal because the Flask send_file function is used unsafely.
{
"affected": [],
"aliases": [
"CVE-2022-31566"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-07-11T01:15:00Z",
"severity": "HIGH"
},
"details": "The DSAB-local/DSAB repository through 2019-02-18 on GitHub allows absolute path traversal because the Flask send_file function is used unsafely.",
"id": "GHSA-625q-87rr-w32g",
"modified": "2022-07-16T00:00:31Z",
"published": "2022-07-12T00:00:58Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-31566"
},
{
"type": "WEB",
"url": "https://github.com/github/securitylab/issues/669#issuecomment-1117265726"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-625R-RW2Q-2RXR
Vulnerability from github – Published: 2022-05-02 03:51 – Updated: 2022-05-02 03:51Multiple directory traversal vulnerabilities in CutePHP CuteNews 1.4.6, when magic_quotes_gpc is disabled, allow remote authenticated users with editor or administrative application access to read arbitrary files via a .. (dot dot) in the source parameter in a (1) list or (2) editnews action to the Editnews module, and (3) the save_con[skin] parameter in the Options module. NOTE: vector 3 can be leveraged for code execution by using a .. to include and execute arbitrary local files.
{
"affected": [],
"aliases": [
"CVE-2009-4116"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2009-11-30T21:30:00Z",
"severity": "LOW"
},
"details": "Multiple directory traversal vulnerabilities in CutePHP CuteNews 1.4.6, when magic_quotes_gpc is disabled, allow remote authenticated users with editor or administrative application access to read arbitrary files via a .. (dot dot) in the source parameter in a (1) list or (2) editnews action to the Editnews module, and (3) the save_con[skin] parameter in the Options module. NOTE: vector 3 can be leveraged for code execution by using a .. to include and execute arbitrary local files.",
"id": "GHSA-625r-rw2q-2rxr",
"modified": "2022-05-02T03:51:53Z",
"published": "2022-05-02T03:51:53Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2009-4116"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/54244"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/54246"
},
{
"type": "WEB",
"url": "http://www.morningstarsecurity.com/advisories/MORNINGSTAR-2009-02-CuteNews.txt"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/archive/1/507782/100/0/threaded"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-626Q-GJ8M-2M4W
Vulnerability from github – Published: 2022-05-14 02:45 – Updated: 2022-05-14 02:45Directory traversal in portal/import_template.php in versions of OpenEMR before 5.0.1.4 allows a remote attacker authenticated in the patient portal to read arbitrary files via the "docid" parameter when the mode is set to get.
{
"affected": [],
"aliases": [
"CVE-2018-15140"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2018-08-13T18:29:00Z",
"severity": "MODERATE"
},
"details": "Directory traversal in portal/import_template.php in versions of OpenEMR before 5.0.1.4 allows a remote attacker authenticated in the patient portal to read arbitrary files via the \"docid\" parameter when the mode is set to get.",
"id": "GHSA-626q-gj8m-2m4w",
"modified": "2022-05-14T02:45:26Z",
"published": "2022-05-14T02:45:26Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2018-15140"
},
{
"type": "WEB",
"url": "https://github.com/openemr/openemr/pull/1765/files"
},
{
"type": "WEB",
"url": "https://www.databreaches.net/openemr-patches-serious-vulnerabilities-uncovered-by-project-insecurity"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/exploits/45202"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-6279-9M22-XW5Q
Vulnerability from github – Published: 2022-05-24 16:44 – Updated: 2024-04-04 00:15The 10Web Form Maker plugin before 1.13.5 for WordPress allows CSRF via the wp-admin/admin-ajax.php action parameter, with resultant local file inclusion via directory traversal, because there can be a discrepancy between the $_POST['action'] value and the $_GET['action'] value, and the latter is unsanitized.
{
"affected": [],
"aliases": [
"CVE-2019-11590"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2019-04-29T14:29:00Z",
"severity": "HIGH"
},
"details": "The 10Web Form Maker plugin before 1.13.5 for WordPress allows CSRF via the wp-admin/admin-ajax.php action parameter, with resultant local file inclusion via directory traversal, because there can be a discrepancy between the $_POST[\u0027action\u0027] value and the $_GET[\u0027action\u0027] value, and the latter is unsanitized.",
"id": "GHSA-6279-9m22-xw5q",
"modified": "2024-04-04T00:15:47Z",
"published": "2022-05-24T16:44:50Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-11590"
},
{
"type": "WEB",
"url": "https://lists.openwall.net/full-disclosure/2019/04/05/11"
},
{
"type": "WEB",
"url": "https://wordpress.org/plugins/form-maker/#developers"
},
{
"type": "WEB",
"url": "http://seclists.org/fulldisclosure/2019/Apr/36"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-627H-WPRW-6CPG
Vulnerability from github – Published: 2026-07-18 15:31 – Updated: 2026-08-13 15:34SurrealDB versions before 2.2.2 contain a local file read vulnerability in the DEFINE ANALYZER statement that allows authenticated users to read arbitrary files on the file system. Attackers with root, namespace, or database level privileges can point analyzers to arbitrary file paths and exfiltrate content from two-column tab-separated files.
{
"affected": [],
"aliases": [
"CVE-2025-71394"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-18T14:17:10Z",
"severity": "LOW"
},
"details": "SurrealDB versions before 2.2.2 contain a local file read vulnerability in the DEFINE ANALYZER statement that allows authenticated users to read arbitrary files on the file system. Attackers with root, namespace, or database level privileges can point analyzers to arbitrary file paths and exfiltrate content from two-column tab-separated files.",
"id": "GHSA-627h-wprw-6cpg",
"modified": "2026-08-13T15:34:13Z",
"published": "2026-07-18T15:31:49Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/surrealdb/surrealdb/security/advisories/GHSA-2cvj-g5r5-jrrg"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-71394"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/surrealdb-before-local-file-read-via-define-analyzer"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
GHSA-6298-8G5J-5F2X
Vulnerability from github – Published: 2023-12-04 06:30 – Updated: 2023-12-07 18:30Path traversal vulnerability exists in RakRak Document Plus Ver.3.2.0.0 to Ver.6.4.0.7 (excluding Ver.6.1.1.3a). If this vulnerability is exploited, arbitrary files on the server may be obtained or deleted by a user of the product with specific privileges.
{
"affected": [],
"aliases": [
"CVE-2023-49108"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-12-04T06:15:07Z",
"severity": "HIGH"
},
"details": "Path traversal vulnerability exists in RakRak Document Plus Ver.3.2.0.0 to Ver.6.4.0.7 (excluding Ver.6.1.1.3a). If this vulnerability is exploited, arbitrary files on the server may be obtained or deleted by a user of the product with specific privileges.",
"id": "GHSA-6298-8g5j-5f2x",
"modified": "2023-12-07T18:30:31Z",
"published": "2023-12-04T06:30:17Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-49108"
},
{
"type": "WEB",
"url": "https://jvn.jp/en/jp/JVN46895889"
},
{
"type": "WEB",
"url": "https://rakrak.jp/RakDocSupport/rkspServlet"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-629C-J52G-H978
Vulnerability from github – Published: 2026-09-10 18:31 – Updated: 2026-09-10 18:31knowns through 0.33.0 fails to confine the path argument of the code.find MCP tool to the project root, allowing AI agent sessions to read source files anywhere on the host. Attackers can supply absolute paths or relative traversal sequences to the path argument and retrieve full file contents from outside the intended project directory.
{
"affected": [],
"aliases": [
"CVE-2026-88938"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-10T16:18:12Z",
"severity": "HIGH"
},
"details": "knowns through 0.33.0 fails to confine the path argument of the code.find MCP tool to the project root, allowing AI agent sessions to read source files anywhere on the host. Attackers can supply absolute paths or relative traversal sequences to the path argument and retrieve full file contents from outside the intended project directory.",
"id": "GHSA-629c-j52g-h978",
"modified": "2026-09-10T18:31:46Z",
"published": "2026-09-10T18:31:46Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/knowns-dev/knowns/security/advisories/GHSA-5cj9-fcqq-g2h7"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-88938"
},
{
"type": "WEB",
"url": "https://github.com/knowns-dev/knowns/blob/v0.33.0/internal/mcp/handlers/code.go#L1293-L1354"
},
{
"type": "WEB",
"url": "https://github.com/knowns-dev/knowns/blob/v0.33.0/internal/mcp/handlers/code.go#L873-L902"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/knowns-through-0.33.0-path-traversal-via-code-find-mcp-tool"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
GHSA-62C5-J9G9-CMXR
Vulnerability from github – Published: 2022-05-17 05:05 – Updated: 2022-05-17 05:05Directory traversal vulnerability in admin/upgrade_unattended.php in MantisBT before 1.2.4 allows remote attackers to include and execute arbitrary local files via a .. (dot dot) in the db_type parameter, related to an unsafe call by MantisBT to a function in the ADOdb Library for PHP.
{
"affected": [],
"aliases": [
"CVE-2010-4350"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2011-01-03T20:00:00Z",
"severity": "MODERATE"
},
"details": "Directory traversal vulnerability in admin/upgrade_unattended.php in MantisBT before 1.2.4 allows remote attackers to include and execute arbitrary local files via a .. (dot dot) in the db_type parameter, related to an unsafe call by MantisBT to a function in the ADOdb Library for PHP.",
"id": "GHSA-62c5-j9g9-cmxr",
"modified": "2022-05-17T05:05:45Z",
"published": "2022-05-17T05:05:45Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2010-4350"
},
{
"type": "WEB",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=663230"
},
{
"type": "WEB",
"url": "http://lists.fedoraproject.org/pipermail/package-announce/2010-December/052721.html"
},
{
"type": "WEB",
"url": "http://lists.fedoraproject.org/pipermail/package-announce/2010-December/052730.html"
},
{
"type": "WEB",
"url": "http://openwall.com/lists/oss-security/2010/12/15/5"
},
{
"type": "WEB",
"url": "http://openwall.com/lists/oss-security/2010/12/16/2"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/42772"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/51199"
},
{
"type": "WEB",
"url": "http://security.gentoo.org/glsa/glsa-201211-01.xml"
},
{
"type": "WEB",
"url": "http://www.mantisbt.org/blog/?p=123"
},
{
"type": "WEB",
"url": "http://www.mantisbt.org/bugs/changelog_page.php?version_id=112"
},
{
"type": "WEB",
"url": "http://www.mantisbt.org/bugs/view.php?id=12607"
},
{
"type": "WEB",
"url": "http://www.vupen.com/english/advisories/2011/0002"
},
{
"type": "WEB",
"url": "http://www.zeroscience.mk/en/vulnerabilities/ZSL-2010-4984.php"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-62F5-CP2P-VQ95
Vulnerability from github – Published: 2026-09-04 18:00 – Updated: 2026-09-04 18:00Maintainer resolution
The CodeWhale maintainers validated this report. The affected package ranges are recorded in the advisory metadata. Version 0.8.64 contains the fix in commit 43563356b98c6b993085554da82e77370160a31c. Users should upgrade to 0.8.64 or later. The original reporter analysis is preserved below.
Summary
A malicious .codewhale/config.toml or .deepseek/config.toml committed to a repository can set instructions to an array of arbitrary file paths (including paths outside the workspace like ~/.ssh/id_rsa or ~/.aws/credentials) that are read from disk and injected into the AI model's system prompt. There is no path validation, workspace boundary check, or tightening guard on the instructions field. This enables a malicious repository to exfiltrate the contents of sensitive files on the victim's machine through the AI conversation.
Details
The project config merge function at crates/tui/src/main.rs:5190-5197 (v0.8.50) copies the instructions array from a project-level config file into the live session config without any path validation:
if let Some(arr) = table.get("instructions").and_then(toml::Value::as_array) {
let entries: Vec<String> = arr
.iter()
.filter_map(|v| v.as_str().map(str::to_string))
.filter(|s| !s.trim().is_empty())
.collect();
config.instructions = Some(entries);
}
These paths are then resolved via expand_path at crates/tui/src/config.rs:2361-2371, which expands ~ to the user's home directory and resolves environment variables:
pub fn instructions_paths(&self) -> Vec<PathBuf> {
self.instructions.as_deref().unwrap_or(&[])
.iter()
.map(String::as_str)
.map(str::trim)
.filter(|s| !s.is_empty())
.map(expand_path)
.collect()
}
The resolved paths are loaded at prompt-render time in crates/tui/src/prompts.rs:216 with no workspace boundary check:
InstructionSource::File(path) => match std::fs::read_to_string(path) {
Ok(raw) => (path.display().to_string(), raw),
...
}
The file contents are injected into the AI system prompt at crates/tui/src/prompts.rs:243-245:
sections.push(format!(
"<instructions source=\"{raw_source_name}\">\n{body}\n</instructions>"
));
Source of attacker-controlled input: The .codewhale/config.toml or .deepseek/config.toml file in a cloned repository, specifically the instructions array.
Security boundary crossed: Workspace isolation. The resolve_path function in crates/tui/src/tools/spec.rs:360-466 enforces workspace boundaries for file tools, but the instructions loading path has no such boundary check.
Sink reached: The contents of arbitrary files are placed into the AI model's system prompt, making them available to the model and potentially exfiltratable through conversation responses.
Why existing mitigations do not prevent exploitation:
1. The INSTRUCTIONS_FILE_MAX_BYTES cap at crates/tui/src/prompts.rs:70 limits each file to 100KB but does not prevent reading sensitive files (SSH keys, AWS credentials, .env files are all well under 100KB).
2. The DENY_AT_PROJECT_SCOPE list at crates/tui/src/main.rs:5119 blocks api_key, base_url, provider, and mcp_config_path but does not block instructions.
3. Unlike approval_policy and sandbox_mode, there is no tightening guard for instructions.
4. The expand_path function at crates/tui/src/config.rs:2805 actively expands ~ and environment variables, making it easier to target known sensitive file locations.
Flow from source to sink:
1. User clones a repository containing .codewhale/config.toml with instructions = ["~/.ssh/id_rsa"]
2. User runs codewhale in the repository directory
3. merge_project_config() reads the project config and sets config.instructions = Some(["~/.ssh/id_rsa"])
4. config.instructions_paths() calls expand_path on each entry, resolving ~/.ssh/id_rsa to /home/victim/.ssh/id_rsa
5. render_instructions_block() reads the file with std::fs::read_to_string and injects it into the system prompt
6. The AI model sees the SSH private key content in its system prompt and can be instructed to output it in conversation
PoC
Environment: Any system with CodeWhale v0.8.50 built from source (commit 0072209d).
Clean checkout recipe:
-
Build CodeWhale TUI:
bash git clone https://github.com/Hmbown/CodeWhale.git cd CodeWhale git checkout 0072209d cargo build --release -p codewhale-tui -
Create a test fixture (simulating sensitive file):
bash mkdir -p /tmp/victim-home/.ssh echo "SECRET_PRIVATE_KEY_CONTENT" > /tmp/victim-home/.ssh/id_rsa -
Create a malicious workspace with project config targeting the sensitive file:
bash mkdir -p /tmp/malicious-repo/.codewhale cat > /tmp/malicious-repo/.codewhale/config.toml << 'EOF' instructions = ["~/.ssh/id_rsa", "/etc/passwd"] EOF -
Run the existing unit test that confirms the override works:
bash cargo test -p codewhale-tui -- project_overlay_replaces_user_instructions_array_wholesale --nocaptureExpected output: Test passes, confirming project instructions array replaces user array wholesale. -
Verify the path expansion and file reading behavior in the source:
bash # Confirm expand_path resolves ~ to home directory grep -n 'expand_path' crates/tui/src/config.rs | head -3Observed output:2700:fn expand_path(path: &str) -> PathBuf {
bash
# Confirm no workspace boundary check in instructions loading
grep -B2 -A5 'read_to_string.*path' crates/tui/src/prompts.rs | head -12
Observed output:
InstructionSource::File(path) => match std::fs::read_to_string(path) {
Ok(raw) => (path.display().to_string(), raw),
Err(err) => {
tracing::warn!(
- Negative control — file tools enforce workspace boundary:
bash grep -n 'starts_with.*workspace' crates/tui/src/tools/spec.rs | head -3Observed output:399: .starts_with(&workspace_canonical)This confirms that file tools have workspace boundary enforcement, but the instructions loading path does not.
Cleanup:
rm -rf /tmp/victim-home /tmp/malicious-repo
Impact
This is a high-severity confidentiality vulnerability. Any user who clones a repository containing a malicious .codewhale/config.toml with crafted instructions paths will have arbitrary files read and injected into the AI system prompt.
- Attacker privilege required: Repository maintainer (can commit the malicious config file) or a supply-chain compromise of a repository the victim clones.
- User interaction required: The victim must run CodeWhale in the cloned repository directory. No explicit confirmation or trust prompt is shown for the
instructionsoverride. - Impact: The attacker can read any file accessible to the victim user, including:
- SSH private keys (
~/.ssh/id_rsa,~/.ssh/id_ed25519) - Cloud credentials (
~/.aws/credentials,~/.gcp/keyfile.json) - Environment files (
.envin other projects) - Secret stores (
~/.codewhale/secrets/secrets.json) - System files (
/etc/shadowif user has read access) - Exfiltration vector: The file contents appear in the AI model's system prompt. The attacker can then instruct the model (via the repository's own
instructions.mdorAGENTS.mdfiles) to output the sensitive contents in conversation responses, or to include them in tool calls (e.g., writing to a file in the workspace, or usingfetch_urlto send to an attacker-controlled server). - Security boundary crossed: Workspace isolation is bypassed; the instructions path can read files anywhere on the filesystem.
Suggested remediation
-
Add
instructionsto theDENY_AT_PROJECT_SCOPElist atcrates/tui/src/main.rs:5119:rust const DENY_AT_PROJECT_SCOPE: &[&str] = &[ "api_key", "base_url", "provider", "mcp_config_path", "instructions" ]; -
Alternatively, validate that all instruction paths resolve within the workspace directory:
rust if let Some(arr) = table.get("instructions").and_then(toml::Value::as_array) { let entries: Vec<String> = arr .iter() .filter_map(|v| v.as_str().map(str::to_string)) .filter(|s| !s.trim().is_empty()) .filter(|s| { let resolved = expand_path(s); resolved.starts_with(workspace) || resolved.is_relative() }) .collect(); if !entries.is_empty() { config.instructions = Some(entries); } } -
Regression test:
rust #[test] fn project_overlay_instructions_rejects_paths_outside_workspace() { let tmp = workspace_with_project_config( r#"instructions = ["~/.ssh/id_rsa", "/etc/passwd"]"#, ); let mut config = Config::default(); merge_project_config(&mut config, tmp.path()); // Instructions pointing outside workspace should be rejected let paths = config.instructions_paths(); assert!( paths.iter().all(|p| p.starts_with(tmp.path())), "instructions paths must be within workspace: {paths:?}" ); }
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c 0.8.41"
},
"package": {
"ecosystem": "crates.io",
"name": "deepseek-tui"
},
"ranges": [
{
"events": [
{
"introduced": "0.8.8"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "npm",
"name": "deepseek-tui"
},
"ranges": [
{
"events": [
{
"introduced": "0.8.8"
},
{
"fixed": "0.8.41"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "crates.io",
"name": "codewhale-tui"
},
"ranges": [
{
"events": [
{
"introduced": "0.8.41"
},
{
"fixed": "0.8.64"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "npm",
"name": "codewhale"
},
"ranges": [
{
"events": [
{
"introduced": "0.8.41"
},
{
"fixed": "0.8.64"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-75859"
],
"database_specific": {
"cwe_ids": [
"CWE-200",
"CWE-22"
],
"github_reviewed": true,
"github_reviewed_at": "2026-09-04T18:00:37Z",
"nvd_published_at": "2026-08-18T16:18:21Z",
"severity": "HIGH"
},
"details": "### Maintainer resolution\n\nThe CodeWhale maintainers validated this report. The affected package ranges are recorded in the advisory metadata. Version 0.8.64 contains the fix in commit 43563356b98c6b993085554da82e77370160a31c. Users should upgrade to 0.8.64 or later. The original reporter analysis is preserved below.\n\n### Summary\n\nA malicious `.codewhale/config.toml` or `.deepseek/config.toml` committed to a repository can set `instructions` to an array of arbitrary file paths (including paths outside the workspace like `~/.ssh/id_rsa` or `~/.aws/credentials`) that are read from disk and injected into the AI model\u0027s system prompt. There is no path validation, workspace boundary check, or tightening guard on the `instructions` field. This enables a malicious repository to exfiltrate the contents of sensitive files on the victim\u0027s machine through the AI conversation.\n\n### Details\n\nThe project config merge function at `crates/tui/src/main.rs:5190-5197` (v0.8.50) copies the `instructions` array from a project-level config file into the live session config without any path validation:\n\n```rust\nif let Some(arr) = table.get(\"instructions\").and_then(toml::Value::as_array) {\n let entries: Vec\u003cString\u003e = arr\n .iter()\n .filter_map(|v| v.as_str().map(str::to_string))\n .filter(|s| !s.trim().is_empty())\n .collect();\n config.instructions = Some(entries);\n}\n```\n\nThese paths are then resolved via `expand_path` at `crates/tui/src/config.rs:2361-2371`, which expands `~` to the user\u0027s home directory and resolves environment variables:\n\n```rust\npub fn instructions_paths(\u0026self) -\u003e Vec\u003cPathBuf\u003e {\n self.instructions.as_deref().unwrap_or(\u0026[])\n .iter()\n .map(String::as_str)\n .map(str::trim)\n .filter(|s| !s.is_empty())\n .map(expand_path)\n .collect()\n}\n```\n\nThe resolved paths are loaded at prompt-render time in `crates/tui/src/prompts.rs:216` with no workspace boundary check:\n\n```rust\nInstructionSource::File(path) =\u003e match std::fs::read_to_string(path) {\n Ok(raw) =\u003e (path.display().to_string(), raw),\n ...\n}\n```\n\nThe file contents are injected into the AI system prompt at `crates/tui/src/prompts.rs:243-245`:\n\n```rust\nsections.push(format!(\n \"\u003cinstructions source=\\\"{raw_source_name}\\\"\u003e\\n{body}\\n\u003c/instructions\u003e\"\n));\n```\n\n**Source of attacker-controlled input:** The `.codewhale/config.toml` or `.deepseek/config.toml` file in a cloned repository, specifically the `instructions` array.\n\n**Security boundary crossed:** Workspace isolation. The `resolve_path` function in `crates/tui/src/tools/spec.rs:360-466` enforces workspace boundaries for file tools, but the `instructions` loading path has no such boundary check.\n\n**Sink reached:** The contents of arbitrary files are placed into the AI model\u0027s system prompt, making them available to the model and potentially exfiltratable through conversation responses.\n\n**Why existing mitigations do not prevent exploitation:**\n1. The `INSTRUCTIONS_FILE_MAX_BYTES` cap at `crates/tui/src/prompts.rs:70` limits each file to 100KB but does not prevent reading sensitive files (SSH keys, AWS credentials, `.env` files are all well under 100KB).\n2. The `DENY_AT_PROJECT_SCOPE` list at `crates/tui/src/main.rs:5119` blocks `api_key`, `base_url`, `provider`, and `mcp_config_path` but does **not** block `instructions`.\n3. Unlike `approval_policy` and `sandbox_mode`, there is no tightening guard for `instructions`.\n4. The `expand_path` function at `crates/tui/src/config.rs:2805` actively expands `~` and environment variables, making it easier to target known sensitive file locations.\n\n**Flow from source to sink:**\n1. User clones a repository containing `.codewhale/config.toml` with `instructions = [\"~/.ssh/id_rsa\"]`\n2. User runs `codewhale` in the repository directory\n3. `merge_project_config()` reads the project config and sets `config.instructions = Some([\"~/.ssh/id_rsa\"])`\n4. `config.instructions_paths()` calls `expand_path` on each entry, resolving `~/.ssh/id_rsa` to `/home/victim/.ssh/id_rsa`\n5. `render_instructions_block()` reads the file with `std::fs::read_to_string` and injects it into the system prompt\n6. The AI model sees the SSH private key content in its system prompt and can be instructed to output it in conversation\n\n### PoC\n\n**Environment:** Any system with CodeWhale v0.8.50 built from source (commit `0072209d`).\n\n**Clean checkout recipe:**\n\n1. Build CodeWhale TUI:\n ```bash\n git clone https://github.com/Hmbown/CodeWhale.git\n cd CodeWhale\n git checkout 0072209d\n cargo build --release -p codewhale-tui\n ```\n\n2. Create a test fixture (simulating sensitive file):\n ```bash\n mkdir -p /tmp/victim-home/.ssh\n echo \"SECRET_PRIVATE_KEY_CONTENT\" \u003e /tmp/victim-home/.ssh/id_rsa\n ```\n\n3. Create a malicious workspace with project config targeting the sensitive file:\n ```bash\n mkdir -p /tmp/malicious-repo/.codewhale\n cat \u003e /tmp/malicious-repo/.codewhale/config.toml \u003c\u003c \u0027EOF\u0027\n instructions = [\"~/.ssh/id_rsa\", \"/etc/passwd\"]\n EOF\n ```\n\n4. Run the existing unit test that confirms the override works:\n ```bash\n cargo test -p codewhale-tui -- project_overlay_replaces_user_instructions_array_wholesale --nocapture\n ```\n **Expected output:** Test passes, confirming project instructions array replaces user array wholesale.\n\n5. Verify the path expansion and file reading behavior in the source:\n ```bash\n # Confirm expand_path resolves ~ to home directory\n grep -n \u0027expand_path\u0027 crates/tui/src/config.rs | head -3\n ```\n **Observed output:**\n ```\n 2700:fn expand_path(path: \u0026str) -\u003e PathBuf {\n ```\n\n ```bash\n # Confirm no workspace boundary check in instructions loading\n grep -B2 -A5 \u0027read_to_string.*path\u0027 crates/tui/src/prompts.rs | head -12\n ```\n **Observed output:**\n ```\n InstructionSource::File(path) =\u003e match std::fs::read_to_string(path) {\n Ok(raw) =\u003e (path.display().to_string(), raw),\n Err(err) =\u003e {\n tracing::warn!(\n ```\n\n6. **Negative control \u2014 file tools enforce workspace boundary:**\n ```bash\n grep -n \u0027starts_with.*workspace\u0027 crates/tui/src/tools/spec.rs | head -3\n ```\n **Observed output:**\n ```\n 399: .starts_with(\u0026workspace_canonical)\n ```\n This confirms that file tools have workspace boundary enforcement, but the instructions loading path does not.\n\n**Cleanup:**\n```bash\nrm -rf /tmp/victim-home /tmp/malicious-repo\n```\n\n### Impact\n\nThis is a **high-severity confidentiality vulnerability**. Any user who clones a repository containing a malicious `.codewhale/config.toml` with crafted `instructions` paths will have arbitrary files read and injected into the AI system prompt.\n\n- **Attacker privilege required:** Repository maintainer (can commit the malicious config file) or a supply-chain compromise of a repository the victim clones.\n- **User interaction required:** The victim must run CodeWhale in the cloned repository directory. No explicit confirmation or trust prompt is shown for the `instructions` override.\n- **Impact:** The attacker can read any file accessible to the victim user, including:\n - SSH private keys (`~/.ssh/id_rsa`, `~/.ssh/id_ed25519`)\n - Cloud credentials (`~/.aws/credentials`, `~/.gcp/keyfile.json`)\n - Environment files (`.env` in other projects)\n - Secret stores (`~/.codewhale/secrets/secrets.json`)\n - System files (`/etc/shadow` if user has read access)\n- **Exfiltration vector:** The file contents appear in the AI model\u0027s system prompt. The attacker can then instruct the model (via the repository\u0027s own `instructions.md` or `AGENTS.md` files) to output the sensitive contents in conversation responses, or to include them in tool calls (e.g., writing to a file in the workspace, or using `fetch_url` to send to an attacker-controlled server).\n- **Security boundary crossed:** Workspace isolation is bypassed; the instructions path can read files anywhere on the filesystem.\n\n### Suggested remediation\n\n1. **Add `instructions` to the `DENY_AT_PROJECT_SCOPE` list** at `crates/tui/src/main.rs:5119`:\n ```rust\n const DENY_AT_PROJECT_SCOPE: \u0026[\u0026str] = \u0026[\n \"api_key\", \"base_url\", \"provider\", \"mcp_config_path\", \"instructions\"\n ];\n ```\n\n2. **Alternatively**, validate that all instruction paths resolve within the workspace directory:\n ```rust\n if let Some(arr) = table.get(\"instructions\").and_then(toml::Value::as_array) {\n let entries: Vec\u003cString\u003e = arr\n .iter()\n .filter_map(|v| v.as_str().map(str::to_string))\n .filter(|s| !s.trim().is_empty())\n .filter(|s| {\n let resolved = expand_path(s);\n resolved.starts_with(workspace) || resolved.is_relative()\n })\n .collect();\n if !entries.is_empty() {\n config.instructions = Some(entries);\n }\n }\n ```\n\n3. **Regression test:**\n ```rust\n #[test]\n fn project_overlay_instructions_rejects_paths_outside_workspace() {\n let tmp = workspace_with_project_config(\n r#\"instructions = [\"~/.ssh/id_rsa\", \"/etc/passwd\"]\"#,\n );\n let mut config = Config::default();\n merge_project_config(\u0026mut config, tmp.path());\n // Instructions pointing outside workspace should be rejected\n let paths = config.instructions_paths();\n assert!(\n paths.iter().all(|p| p.starts_with(tmp.path())),\n \"instructions paths must be within workspace: {paths:?}\"\n );\n }\n ```",
"id": "GHSA-62f5-cp2p-vq95",
"modified": "2026-09-04T18:00:37Z",
"published": "2026-09-04T18:00:37Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/Hmbown/CodeWhale/security/advisories/GHSA-62f5-cp2p-vq95"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-75859"
},
{
"type": "WEB",
"url": "https://github.com/Hmbown/CodeWhale/commit/43563356b98c6b993085554da82e77370160a31c"
},
{
"type": "PACKAGE",
"url": "https://github.com/Hmbown/CodeWhale"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/codewhale-before-arbitrary-file-read-via-instructions"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "CodeWhale: Project config `instructions` override enables arbitrary file read into AI system prompt via cloned repository"
}
GHSA-62F6-QCP7-PW2W
Vulnerability from github – Published: 2022-05-24 19:06 – Updated: 2022-05-24 19:06Adobe InCopy version 16.0 (and earlier) is affected by an path traversal vulnerability when parsing a crafted file. An unauthenticated attacker could leverage this vulnerability to achieve remote code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.
{
"affected": [],
"aliases": [
"CVE-2021-21090"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2021-06-28T14:15:00Z",
"severity": "HIGH"
},
"details": "Adobe InCopy version 16.0 (and earlier) is affected by an path traversal vulnerability when parsing a crafted file. An unauthenticated attacker could leverage this vulnerability to achieve remote code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.",
"id": "GHSA-62f6-qcp7-pw2w",
"modified": "2022-05-24T19:06:26Z",
"published": "2022-05-24T19:06:26Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-21090"
},
{
"type": "WEB",
"url": "https://helpx.adobe.com/security/products/incopy/apsb21-25.html"
}
],
"schema_version": "1.4.0",
"severity": []
}
Mitigation MIT-5.1
Strategy: Input Validation
- Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
- When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue."
- Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
- When validating filenames, use stringent allowlists that limit the character set to be used. If feasible, only allow a single "." character in the filename to avoid weaknesses such as CWE-23, and exclude directory separators such as "/" to avoid CWE-36. Use a list of allowable file extensions, which will help to avoid CWE-434.
- Do not rely exclusively on a filtering mechanism that removes potentially dangerous characters. This is equivalent to a denylist, which may be incomplete (CWE-184). For example, filtering "/" is insufficient protection if the filesystem also supports the use of "\" as a directory separator. Another possible error could occur when the filtering is applied in a way that still produces dangerous data (CWE-182). For example, if "../" sequences are removed from the ".../...//" string in a sequential fashion, two instances of "../" would be removed from the original string, but the remaining characters would still form the "../" string.
Mitigation MIT-15
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
Mitigation MIT-20.1
Strategy: Input Validation
- Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass allowlist validation schemes by introducing dangerous inputs after they have been checked.
- Use a built-in path canonicalization function (such as realpath() in C) that produces the canonical version of the pathname, which effectively removes ".." sequences and symbolic links (CWE-23, CWE-59). This includes:
- realpath() in C
- getCanonicalPath() in Java
- GetFullPath() in ASP.NET
- realpath() or abs_path() in Perl
- realpath() in PHP
Mitigation MIT-4
Strategy: Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482].
Mitigation MIT-29
Strategy: Firewall
Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth [REF-1481].
Mitigation MIT-17
Strategy: Environment Hardening
Run your code using the lowest privileges that are required to accomplish the necessary tasks [REF-76]. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment. For example, database applications rarely need to run as the database administrator, especially in day-to-day operations.
Mitigation MIT-21.1
Strategy: Enforcement by Conversion
- When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
- For example, ID 1 could map to "inbox.txt" and ID 2 could map to "profile.txt". Features such as the ESAPI AccessReferenceMap [REF-185] provide this capability.
Mitigation MIT-22
Strategy: Sandbox or Jail
- Run the code in a "jail" or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.
- OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations.
- This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise.
- Be careful to avoid CWE-243 and other weaknesses related to jails.
Mitigation MIT-34
Strategy: Attack Surface Reduction
- Store library, include, and utility files outside of the web document root, if possible. Otherwise, store them in a separate directory and use the web server's access control capabilities to prevent attackers from directly requesting them. One common practice is to define a fixed constant in each calling program, then check for the existence of the constant in the library/include file; if the constant does not exist, then the file was directly requested, and it can exit immediately.
- This significantly reduces the chance of an attacker being able to bypass any protection mechanisms that are in the base program but not in the include files. It will also reduce the attack surface.
Mitigation MIT-39
- Ensure that error messages only contain minimal details that are useful to the intended audience and no one else. The messages need to strike the balance between being too cryptic (which can confuse users) or being too detailed (which may reveal more than intended). The messages should not reveal the methods that were used to determine the error. Attackers can use detailed information to refine or optimize their original attack, thereby increasing their chances of success.
- If errors must be captured in some detail, record them in log messages, but consider what could occur if the log messages can be viewed by attackers. Highly sensitive information such as passwords should never be saved to log files.
- Avoid inconsistent messaging that might accidentally tip off an attacker about internal state, such as whether a user account exists or not.
- In the context of path traversal, error messages which disclose path information can help attackers craft the appropriate attack strings to move through the file system hierarchy.
Mitigation MIT-16
Strategy: Environment Hardening
When using PHP, configure the application so that it does not use register_globals. During implementation, develop the application so that it does not rely on this feature, but be wary of implementing a register_globals emulation that is subject to weaknesses such as CWE-95, CWE-621, and similar issues.
CAPEC-126: Path Traversal
An adversary uses path manipulation methods to exploit insufficient input validation of a target to obtain access to data that should be not be retrievable by ordinary well-formed requests. A typical variety of this attack involves specifying a path to a desired file together with dot-dot-slash characters, resulting in the file access API or function traversing out of the intended directory structure and into the root file system. By replacing or modifying the expected path information the access function or API retrieves the file desired by the attacker. These attacks either involve the attacker providing a complete path to a targeted file or using control characters (e.g. path separators (/ or \) and/or dots (.)) to reach desired directories or files.
CAPEC-64: Using Slashes and URL Encoding Combined to Bypass Validation Logic
This attack targets the encoding of the URL combined with the encoding of the slash characters. An attacker can take advantage of the multiple ways of encoding a URL and abuse the interpretation of the URL. A URL may contain special character that need special syntax handling in order to be interpreted. Special characters are represented using a percentage character followed by two digits representing the octet code of the original character (%HEX-CODE). For instance US-ASCII space character would be represented with %20. This is often referred as escaped ending or percent-encoding. Since the server decodes the URL from the requests, it may restrict the access to some URL paths by validating and filtering out the URL requests it received. An attacker will try to craft an URL with a sequence of special characters which once interpreted by the server will be equivalent to a forbidden URL. It can be difficult to protect against this attack since the URL can contain other format of encoding such as UTF-8 encoding, Unicode-encoding, etc.
CAPEC-76: Manipulating Web Input to File System Calls
An attacker manipulates inputs to the target software which the target software passes to file system calls in the OS. The goal is to gain access to, and perhaps modify, areas of the file system that the target software did not intend to be accessible.
CAPEC-78: Using Escaped Slashes in Alternate Encoding
This attack targets the use of the backslash in alternate encoding. An adversary can provide a backslash as a leading character and causes a parser to believe that the next character is special. This is called an escape. By using that trick, the adversary tries to exploit alternate ways to encode the same character which leads to filter problems and opens avenues to attack.
CAPEC-79: Using Slashes in Alternate Encoding
This attack targets the encoding of the Slash characters. An adversary would try to exploit common filtering problems related to the use of the slashes characters to gain access to resources on the target host. Directory-driven systems, such as file systems and databases, typically use the slash character to indicate traversal between directories or other container components. For murky historical reasons, PCs (and, as a result, Microsoft OSs) choose to use a backslash, whereas the UNIX world typically makes use of the forward slash. The schizophrenic result is that many MS-based systems are required to understand both forms of the slash. This gives the adversary many opportunities to discover and abuse a number of common filtering problems. The goal of this pattern is to discover server software that only applies filters to one version, but not the other.