CWE-22
Allowed-with-ReviewImproper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
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.
13226 vulnerabilities reference this CWE, most recent first.
GHSA-PFR5-CPM3-G35V
Vulnerability from github – Published: 2023-04-11 12:30 – Updated: 2024-08-13 09:30A vulnerability has been identified in TIA Portal V15 (All versions), TIA Portal V16 (All versions), TIA Portal V17 (All versions), TIA Portal V18 (All versions < V18 Update 1). Affected products contain a path traversal vulnerability that could allow the creation or overwrite of arbitrary files in the engineering system. If the user is tricked to open a malicious PC system configuration file, an attacker could exploit this vulnerability to achieve arbitrary code execution.
{
"affected": [],
"aliases": [
"CVE-2023-26293"
],
"database_specific": {
"cwe_ids": [
"CWE-20",
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-04-11T10:15:00Z",
"severity": "HIGH"
},
"details": "A vulnerability has been identified in TIA Portal V15 (All versions), TIA Portal V16 (All versions), TIA Portal V17 (All versions), TIA Portal V18 (All versions \u003c V18 Update 1). Affected products contain a path traversal vulnerability that could allow the creation or overwrite of arbitrary files in the engineering system. If the user is tricked to open a malicious PC system configuration file, an attacker could exploit this vulnerability to achieve arbitrary code execution.",
"id": "GHSA-pfr5-cpm3-g35v",
"modified": "2024-08-13T09:30:50Z",
"published": "2023-04-11T12:30:26Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-26293"
},
{
"type": "WEB",
"url": "https://cert-portal.siemens.com/productcert/html/ssa-116924.html"
},
{
"type": "WEB",
"url": "https://cert-portal.siemens.com/productcert/pdf/ssa-116924.pdf"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L",
"type": "CVSS_V3"
}
]
}
GHSA-PFVW-QGRV-HGV6
Vulnerability from github – Published: 2026-03-10 18:31 – Updated: 2026-03-10 18:31An Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability [CWE-22] vulnerability in Fortinet FortiSOAR Agent Communication Bridge 1.1.0, FortiSOAR Agent Communication Bridge 1.0 all versions may allow an unauthenticated attacker to read files accessible to the fortisoar user on a system where the agent is deployed, via sending a crafted request to the agent port.
{
"affected": [],
"aliases": [
"CVE-2025-54659"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-03-10T18:17:58Z",
"severity": "MODERATE"
},
"details": "An Improper Limitation of a Pathname to a Restricted Directory (\u0027Path Traversal\u0027) vulnerability [CWE-22] vulnerability in Fortinet FortiSOAR Agent Communication Bridge 1.1.0, FortiSOAR Agent Communication Bridge 1.0 all versions may allow an unauthenticated attacker to read files accessible to the fortisoar user on a system where the agent is deployed, via sending a crafted request to the agent port.",
"id": "GHSA-pfvw-qgrv-hgv6",
"modified": "2026-03-10T18:31:18Z",
"published": "2026-03-10T18:31:18Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-54659"
},
{
"type": "WEB",
"url": "https://fortiguard.fortinet.com/psirt/FG-IR-26-084"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-PFWQ-PHCG-673V
Vulnerability from github – Published: 2022-05-24 16:46 – Updated: 2024-04-04 00:42Directory traversal vulnerability in Cybozu Garoon 4.0.0 to 4.10.1 allows remote authenticated attackers to obtain files without access privileges via the application 'Work Flow'.
{
"affected": [],
"aliases": [
"CVE-2019-5936"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2019-05-17T16:29:00Z",
"severity": "MODERATE"
},
"details": "Directory traversal vulnerability in Cybozu Garoon 4.0.0 to 4.10.1 allows remote authenticated attackers to obtain files without access privileges via the application \u0027Work Flow\u0027.",
"id": "GHSA-pfwq-phcg-673v",
"modified": "2024-04-04T00:42:25Z",
"published": "2022-05-24T16:46:03Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-5936"
},
{
"type": "WEB",
"url": "https://kb.cybozu.support/article/35484"
},
{
"type": "WEB",
"url": "http://jvn.jp/en/jp/JVN58849431/index.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-PG4G-CH23-5CH7
Vulnerability from github – Published: 2022-05-24 16:44 – Updated: 2023-02-10 03:30Dell EMC Open Manage System Administrator (OMSA) versions prior to 9.3.0 contain a Directory Traversal Vulnerability. A remote authenticated malicious user with admin privileges could potentially exploit this vulnerability to gain unauthorized access to the file system by exploiting insufficient sanitization of input parameters.
{
"affected": [],
"aliases": [
"CVE-2019-3720"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2019-04-25T21:29:00Z",
"severity": "MODERATE"
},
"details": "Dell EMC Open Manage System Administrator (OMSA) versions prior to 9.3.0 contain a Directory Traversal Vulnerability. A remote authenticated malicious user with admin privileges could potentially exploit this vulnerability to gain unauthorized access to the file system by exploiting insufficient sanitization of input parameters.",
"id": "GHSA-pg4g-ch23-5ch7",
"modified": "2023-02-10T03:30:18Z",
"published": "2022-05-24T16:44:42Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-3720"
},
{
"type": "WEB",
"url": "https://www.dell.com/support/article/us/en/04/sln316915/dsa-2019-060-dell-emc-open-manage-system-administrator-multiple-vulnerabilities?lang=en"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/108092"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-PG4W-G64P-QWHJ
Vulnerability from github – Published: 2026-05-05 19:26 – Updated: 2026-05-05 19:26Summary
attachments: pocs.zip
When Repository::submodules() loads submodule metadata, it prefers the worktree .gitmodules file if that path exists. In the current implementation, the path is read with std::fs::read(), which follows symlinks. As a result, a repository can present a symlinked .gitmodules that points outside the repository, and gitoxide will parse the out-of-repository bytes as submodule configuration.
This is a repository-boundary violation. A caller using the high-level submodule API can believe it is reading repository-local submodule metadata, while the bytes are actually coming from an arbitrary file outside the repository tree.
Root cause analysis
The relevant flow is:
gix/src/repository/location.rsderives the worktree.gitmodulespath asworkdir/.gitmodules.gix/src/repository/submodule.rsreads that path withstd::fs::read(&path)and immediately parses the bytes as a submodule configuration file.Repository::submodules()exposes the parsed entries through the high-level API.
The issue is not in the parser. The issue is that the worktree path is treated as an ordinary file without checking whether it is a symlink, and without checking whether the canonicalized target remains inside the repository worktree.
Because std::fs::read() follows symlinks, a malicious repository can cause gitoxide to ingest bytes from an attacker-chosen location outside the repository. The resulting Submodule objects then expose name, path, and url values derived from that external file.
Reproduction steps
Use the attached PoC zip that contains the pocs/ workspace.
- Unzip the PoC archive.
- Enter
pocs/F001. -
Run:
bash cargo run --quiet -
Compare the output with
pocs/F001/result.txt.
Important outputs include:
gitmodules_symlink=.../victim-repo/.gitmodulessymlink_target=.../outside/modules.confparsed_name=symlinkedparsed_path=deps/symlinkedparsed_url=https://attacker.example/symlinked.git
These outputs show that gitoxide parsed the submodule configuration from the symlink target outside the repository, not from repository-local bytes.
Impact
Confirmed impact:
- out-of-repository bytes can be injected into the result of
Repository::submodules(); - callers can be misled about submodule metadata such as
name,path, andurl; - any downstream workflow that uses those values to decide clone, fetch, update, or policy behavior is operating on attacker-controlled data that did not actually originate from the repository tree.
This report does not claim direct command execution from this code path by itself. The demonstrated impact is metadata injection across the repository boundary.
Recommended fix
A safe fix is to stop silently following symlinks for the worktree .gitmodules path in this loading path.
Reasonable options include:
- use
symlink_metadata()/lstatstyle checks and reject symlinked.gitmoduleswhen loading from the worktree; - canonicalize the target and verify that it still resides under the repository worktree before reading it;
- for security-sensitive callers, prefer loading
.gitmodulesfrom the index orHEADtree rather than following the worktree path.
At minimum, the worktree path should not silently follow symlinks to arbitrary external files.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 0.52.0"
},
"package": {
"ecosystem": "crates.io",
"name": "gitoxide"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.52.1"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "crates.io",
"name": "gix"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.83.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": true,
"github_reviewed_at": "2026-05-05T19:26:09Z",
"nvd_published_at": null,
"severity": "HIGH"
},
"details": "## Summary\nattachments:\n[pocs.zip](https://github.com/user-attachments/files/26431422/pocs.zip)\n\n\nWhen `Repository::submodules()` loads submodule metadata, it prefers the worktree `.gitmodules` file if that path exists. In the current implementation, the path is read with `std::fs::read()`, which follows symlinks. As a result, a repository can present a symlinked `.gitmodules` that points outside the repository, and gitoxide will parse the out-of-repository bytes as submodule configuration.\n\nThis is a repository-boundary violation. A caller using the high-level submodule API can believe it is reading repository-local submodule metadata, while the bytes are actually coming from an arbitrary file outside the repository tree.\n\n## Root cause analysis\n\nThe relevant flow is:\n\n1. [`gix/src/repository/location.rs`](https://github.com/GitoxideLabs/gitoxide/blob/v0.52.0/gix/src/repository/location.rs) derives the worktree `.gitmodules` path as `workdir/.gitmodules`.\n2. [`gix/src/repository/submodule.rs`](https://github.com/GitoxideLabs/gitoxide/blob/v0.52.0/gix/src/repository/submodule.rs) reads that path with `std::fs::read(\u0026path)` and immediately parses the bytes as a submodule configuration file.\n3. `Repository::submodules()` exposes the parsed entries through the high-level API.\n\nThe issue is not in the parser. The issue is that the worktree path is treated as an ordinary file without checking whether it is a symlink, and without checking whether the canonicalized target remains inside the repository worktree.\n\nBecause `std::fs::read()` follows symlinks, a malicious repository can cause gitoxide to ingest bytes from an attacker-chosen location outside the repository. The resulting `Submodule` objects then expose `name`, `path`, and `url` values derived from that external file.\n\n## Reproduction steps\n\nUse the attached PoC zip that contains the `pocs/` workspace.\n\n1. Unzip the PoC archive.\n2. Enter `pocs/F001`.\n3. Run:\n \n ```bash\n cargo run --quiet\n ```\n \n4. Compare the output with `pocs/F001/result.txt`.\n\nImportant outputs include:\n\n- `gitmodules_symlink=.../victim-repo/.gitmodules`\n- `symlink_target=.../outside/modules.conf`\n- `parsed_name=symlinked`\n- `parsed_path=deps/symlinked`\n- `parsed_url=https://attacker.example/symlinked.git`\n\nThese outputs show that gitoxide parsed the submodule configuration from the symlink target outside the repository, not from repository-local bytes.\n\n## Impact\n\nConfirmed impact:\n\n- out-of-repository bytes can be injected into the result of `Repository::submodules()`;\n- callers can be misled about submodule metadata such as `name`, `path`, and `url`;\n- any downstream workflow that uses those values to decide clone, fetch, update, or policy behavior is operating on attacker-controlled data that did not actually originate from the repository tree.\n\nThis report does **not** claim direct command execution from this code path by itself. The demonstrated impact is metadata injection across the repository boundary.\n\n## Recommended fix\n\nA safe fix is to stop silently following symlinks for the worktree `.gitmodules` path in this loading path.\n\nReasonable options include:\n\n1. use `symlink_metadata()` / `lstat`style checks and reject symlinked `.gitmodules` when loading from the worktree;\n2. canonicalize the target and verify that it still resides under the repository worktree before reading it;\n3. for security-sensitive callers, prefer loading `.gitmodules` from the index or `HEAD` tree rather than following the worktree path.\n\nAt minimum, the worktree path should not silently follow symlinks to arbitrary external files.",
"id": "GHSA-pg4w-g64p-qwhj",
"modified": "2026-05-05T19:26:09Z",
"published": "2026-05-05T19:26:09Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/GitoxideLabs/gitoxide/security/advisories/GHSA-pg4w-g64p-qwhj"
},
{
"type": "PACKAGE",
"url": "https://github.com/GitoxideLabs/gitoxide"
}
],
"schema_version": "1.4.0",
"severity": [
{
"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/E:P",
"type": "CVSS_V4"
}
],
"summary": "gix and gitoxide\u0027s symlinked .gitmodules are followed and parsed from outside of the repository"
}
GHSA-PG6V-35J6-X9WW
Vulnerability from github – Published: 2022-05-17 03:13 – Updated: 2022-05-17 03:13Directory traversal vulnerability in the PreBoot service in Novell ZENworks Configuration Management (ZCM) 11.2 allows remote attackers to read arbitrary files via a .. (dot dot) in a preboot update pathname, aka ZDI-CAN-1595.
{
"affected": [],
"aliases": [
"CVE-2013-3706"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2014-03-06T11:55:00Z",
"severity": "MODERATE"
},
"details": "Directory traversal vulnerability in the PreBoot service in Novell ZENworks Configuration Management (ZCM) 11.2 allows remote attackers to read arbitrary files via a .. (dot dot) in a preboot update pathname, aka ZDI-CAN-1595.",
"id": "GHSA-pg6v-35j6-x9ww",
"modified": "2022-05-17T03:13:10Z",
"published": "2022-05-17T03:13:10Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2013-3706"
},
{
"type": "WEB",
"url": "http://www.novell.com/support/kb/doc.php?id=7014663"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/65912"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-PG7J-99GM-6WWX
Vulnerability from github – Published: 2022-05-24 17:24 – Updated: 2024-01-13 06:30A path traversal vulnerability exists in Pulse Connect Secure <9.1R8 which allows an authenticated attacker to read arbitrary files via the administrator web interface.
{
"affected": [],
"aliases": [
"CVE-2020-8221"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2020-07-30T13:15:00Z",
"severity": "MODERATE"
},
"details": "A path traversal vulnerability exists in Pulse Connect Secure \u003c9.1R8 which allows an authenticated attacker to read arbitrary files via the administrator web interface.",
"id": "GHSA-pg7j-99gm-6wwx",
"modified": "2024-01-13T06:30:22Z",
"published": "2022-05-24T17:24:46Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-8221"
},
{
"type": "WEB",
"url": "https://kb.pulsesecure.net/articles/Pulse_Security_Advisories/SA44516"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-PG7P-MR9Q-X687
Vulnerability from github – Published: 2022-05-02 06:17 – Updated: 2022-05-02 06:17Directory traversal vulnerability in the Abbreviations Manager (com_abbrev) component 1.1 for Joomla! allows remote attackers to include and execute arbitrary local files via a .. (dot dot) in the controller parameter to index.php. NOTE: some of these details are obtained from third party information.
{
"affected": [],
"aliases": [
"CVE-2010-0985"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2010-03-16T19:30:00Z",
"severity": "HIGH"
},
"details": "Directory traversal vulnerability in the Abbreviations Manager (com_abbrev) component 1.1 for Joomla! allows remote attackers to include and execute arbitrary local files via a .. (dot dot) in the controller parameter to index.php. NOTE: some of these details are obtained from third party information.",
"id": "GHSA-pg7p-mr9q-x687",
"modified": "2022-05-02T06:17:49Z",
"published": "2022-05-02T06:17:49Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2010-0985"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/55348"
},
{
"type": "WEB",
"url": "http://osvdb.org/61458"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/37834"
},
{
"type": "WEB",
"url": "http://www.exploit-db.com/exploits/10948"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/37560"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-PG7Q-39QH-P6JG
Vulnerability from github – Published: 2022-05-14 03:01 – Updated: 2022-05-14 03:01beep version 1.3 and up contains a External Control of File Name or Path vulnerability in --device option that can result in Local unprivileged user can inhibit execution of arbitrary programs by other users, allowing DoS. This attack appear to be exploitable via The system must allow local users to run beep.
{
"affected": [],
"aliases": [
"CVE-2018-1000532"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2018-06-26T16:29:00Z",
"severity": "MODERATE"
},
"details": "beep version 1.3 and up contains a External Control of File Name or Path vulnerability in --device option that can result in Local unprivileged user can inhibit execution of arbitrary programs by other users, allowing DoS. This attack appear to be exploitable via The system must allow local users to run beep.",
"id": "GHSA-pg7q-39qh-p6jg",
"modified": "2022-05-14T03:01:58Z",
"published": "2022-05-14T03:01:58Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2018-1000532"
},
{
"type": "WEB",
"url": "https://github.com/johnath/beep/issues/11#issuecomment-379514298"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-PG8P-96CV-V9CJ
Vulnerability from github – Published: 2024-05-14 15:32 – Updated: 2026-04-02 21:31This issue was addressed through improved state management. This issue is fixed in macOS Sonoma 14.5. An app may be able to read arbitrary files.
{
"affected": [],
"aliases": [
"CVE-2024-27827"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-05-14T15:13:06Z",
"severity": "MODERATE"
},
"details": "This issue was addressed through improved state management. This issue is fixed in macOS Sonoma 14.5. An app may be able to read arbitrary files.",
"id": "GHSA-pg8p-96cv-v9cj",
"modified": "2026-04-02T21:31:41Z",
"published": "2024-05-14T15:32:53Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-27827"
},
{
"type": "WEB",
"url": "https://support.apple.com/en-us/120900"
},
{
"type": "WEB",
"url": "https://support.apple.com/en-us/120903"
},
{
"type": "WEB",
"url": "https://support.apple.com/en-us/HT214106"
},
{
"type": "WEB",
"url": "https://support.apple.com/kb/HT214106"
},
{
"type": "WEB",
"url": "https://support.apple.com/kb/HT214107"
},
{
"type": "WEB",
"url": "http://seclists.org/fulldisclosure/2024/May/12"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
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.