CWE-23
AllowedRelative Path Traversal
Abstraction: Base · Status: Draft
The product uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize sequences such as ".." that can resolve to a location that is outside of that directory.
840 vulnerabilities reference this CWE, most recent first.
GHSA-5H5V-HW44-F6GG
Vulnerability from github – Published: 2024-05-14 20:13 – Updated: 2024-05-14 20:13Impact
Input to functions such as Client.rest.channels.removeBan is not url-encoded, resulting in specially crafted input such as ../../../channels/{id} being normalized into the url /api/v10/channels/{id}, and deleting a channel rather than removing a ban.
Workarounds
- Sanitizing user input, ensuring strings are valid for the purpose they are being used for.
- Encoding input with
encodeURIComponentbefore providing it to the library.
References
OceanicJS/Oceanic@8bf8ee8373b8c565fbdbf70a609aba4fbc1a1ffe
{
"affected": [
{
"package": {
"ecosystem": "npm",
"name": "oceanic.js"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.10.4"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2024-34712"
],
"database_specific": {
"cwe_ids": [
"CWE-22",
"CWE-23"
],
"github_reviewed": true,
"github_reviewed_at": "2024-05-14T20:13:58Z",
"nvd_published_at": "2024-05-14T16:17:26Z",
"severity": "MODERATE"
},
"details": "### Impact\nInput to functions such as `Client.rest.channels.removeBan` is not url-encoded, resulting in specially crafted input such as `../../../channels/{id}` being normalized into the url `/api/v10/channels/{id}`, and deleting a channel rather than removing a ban.\n\n### Workarounds\n* Sanitizing user input, ensuring strings are valid for the purpose they are being used for.\n* Encoding input with `encodeURIComponent` before providing it to the library.\n\n### References\nOceanicJS/Oceanic@8bf8ee8373b8c565fbdbf70a609aba4fbc1a1ffe",
"id": "GHSA-5h5v-hw44-f6gg",
"modified": "2024-05-14T20:13:58Z",
"published": "2024-05-14T20:13:58Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/OceanicJS/Oceanic/security/advisories/GHSA-5h5v-hw44-f6gg"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-34712"
},
{
"type": "WEB",
"url": "https://github.com/OceanicJS/Oceanic/commit/8bf8ee8373b8c565fbdbf70a609aba4fbc1a1ffe"
},
{
"type": "PACKAGE",
"url": "https://github.com/OceanicJS/Oceanic"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "Oceanic allows unsanitized user input to lead to path traversal in URLs"
}
GHSA-5H78-3W3C-QH32
Vulnerability from github – Published: 2025-11-28 09:30 – Updated: 2025-11-28 09:30WebITR developed by Uniong has an Arbitrary File Read vulnerability, allowing authenticated remote attackers to exploit Relative Path Traversal to download arbitrary system files.
{
"affected": [],
"aliases": [
"CVE-2025-13771"
],
"database_specific": {
"cwe_ids": [
"CWE-23"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-11-28T08:15:54Z",
"severity": "HIGH"
},
"details": "WebITR developed by Uniong has an Arbitrary File Read vulnerability, allowing authenticated remote attackers to exploit Relative Path Traversal to download arbitrary system files.",
"id": "GHSA-5h78-3w3c-qh32",
"modified": "2025-11-28T09:30:17Z",
"published": "2025-11-28T09:30:17Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-13771"
},
{
"type": "WEB",
"url": "https://www.twcert.org.tw/en/cp-139-10539-21f45-2.html"
},
{
"type": "WEB",
"url": "https://www.twcert.org.tw/tw/cp-132-10538-6a26d-1.html"
}
],
"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-5Q32-895V-VF2F
Vulnerability from github – Published: 2024-03-08 15:30 – Updated: 2025-06-10 09:30A vulnerability was found in ZKTeco ZKBio Media 2.0.0_x64_2024-01-29-1028. It has been classified as problematic. Affected is an unknown function of the file /pro/common/download of the component Service Port 9999. The manipulation of the argument fileName with the input ../../../../zkbio_media.sql leads to path traversal: '../filedir'. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-256272. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.
{
"affected": [],
"aliases": [
"CVE-2024-2318"
],
"database_specific": {
"cwe_ids": [
"CWE-22",
"CWE-23",
"CWE-24"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-03-08T13:15:07Z",
"severity": "MODERATE"
},
"details": "A vulnerability was found in ZKTeco ZKBio Media 2.0.0_x64_2024-01-29-1028. It has been classified as problematic. Affected is an unknown function of the file /pro/common/download of the component Service Port 9999. The manipulation of the argument fileName with the input ../../../../zkbio_media.sql leads to path traversal: \u0027../filedir\u0027. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-256272. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.",
"id": "GHSA-5q32-895v-vf2f",
"modified": "2025-06-10T09:30:30Z",
"published": "2024-03-08T15:30:32Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-2318"
},
{
"type": "WEB",
"url": "https://gist.github.com/whiteman007/a3b25a7ddf38774329d72930e0cd841a"
},
{
"type": "WEB",
"url": "https://vuldb.com/?ctiid.256272"
},
{
"type": "WEB",
"url": "https://vuldb.com/?id.256272"
},
{
"type": "WEB",
"url": "https://vuldb.com/?submit.288530"
},
{
"type": "WEB",
"url": "https://www.zkteco.com/en/Security_Bulletinsibs/11"
}
],
"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:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/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-5Q6C-FFVG-XCM9
Vulnerability from github – Published: 2024-06-06 21:30 – Updated: 2025-04-08 22:00A vulnerability in mlflow/mlflow version 8.2.1 allows for remote code execution due to improper neutralization of special elements used in an OS command ('Command Injection') within the mlflow.data.http_dataset_source.py module. Specifically, when loading a dataset from a source URL with an HTTP scheme, the filename extracted from the Content-Disposition header or the URL path is used to generate the final file path without proper sanitization. This flaw enables an attacker to control the file path fully by utilizing path traversal or absolute path techniques, such as '../../tmp/poc.txt' or '/tmp/poc.txt', leading to arbitrary file write. Exploiting this vulnerability could allow a malicious user to execute commands on the vulnerable machine, potentially gaining access to data and model information. The issue is fixed in version 2.9.0.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "mlflow"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2.9.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2024-0520"
],
"database_specific": {
"cwe_ids": [
"CWE-22",
"CWE-23"
],
"github_reviewed": true,
"github_reviewed_at": "2024-06-06T22:15:31Z",
"nvd_published_at": "2024-06-06T19:15:51Z",
"severity": "CRITICAL"
},
"details": "A vulnerability in mlflow/mlflow version 8.2.1 allows for remote code execution due to improper neutralization of special elements used in an OS command (\u0027Command Injection\u0027) within the `mlflow.data.http_dataset_source.py` module. Specifically, when loading a dataset from a source URL with an HTTP scheme, the filename extracted from the `Content-Disposition` header or the URL path is used to generate the final file path without proper sanitization. This flaw enables an attacker to control the file path fully by utilizing path traversal or absolute path techniques, such as \u0027../../tmp/poc.txt\u0027 or \u0027/tmp/poc.txt\u0027, leading to arbitrary file write. Exploiting this vulnerability could allow a malicious user to execute commands on the vulnerable machine, potentially gaining access to data and model information. The issue is fixed in version 2.9.0.",
"id": "GHSA-5q6c-ffvg-xcm9",
"modified": "2025-04-08T22:00:47Z",
"published": "2024-06-06T21:30:35Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-0520"
},
{
"type": "WEB",
"url": "https://github.com/mlflow/mlflow/commit/400c226953b4568f4361bc0a0c223511652c2b9d"
},
{
"type": "PACKAGE",
"url": "https://github.com/mlflow/mlflow"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/mlflow/PYSEC-2024-239.yaml"
},
{
"type": "WEB",
"url": "https://huntr.com/bounties/93e470d7-b6f0-409b-af63-49d3e2a26dbc"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
"type": "CVSS_V3"
}
],
"summary": "Remote code execution in mlflow"
}
GHSA-5Q89-432M-P2WV
Vulnerability from github – Published: 2025-09-24 15:31 – Updated: 2025-09-24 15:31nncp before 8.12.0 allows path traversal (for reading or writing) during freqing and file saving via a crafted path in packet data.
{
"affected": [],
"aliases": [
"CVE-2025-60020"
],
"database_specific": {
"cwe_ids": [
"CWE-23"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-09-24T13:15:36Z",
"severity": "MODERATE"
},
"details": "nncp before 8.12.0 allows path traversal (for reading or writing) during freqing and file saving via a crafted path in packet data.",
"id": "GHSA-5q89-432m-p2wv",
"modified": "2025-09-24T15:31:13Z",
"published": "2025-09-24T15:31:13Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-60020"
},
{
"type": "WEB",
"url": "http://lists.cypherpunks.su/archive/nncp-devel/CAO-d-4riai9EZx4gVfekow-BCtTn07k8BB1ZdsopPVw=scWD1A@mail.gmail.com/T/#md678a00df1020bb811f47f42ef33c54b789cddd7"
},
{
"type": "WEB",
"url": "http://www.nncpgo.org/Release-8_005f12_005f0.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-5W99-758F-6JVM
Vulnerability from github – Published: 2026-08-27 21:31 – Updated: 2026-08-27 21:31A relative path traversal issue in the zip extraction functionality in AWS diagram-as-code (awsdac) in versions 0.10 through 0.23 can allow a third party to write arbitrary files to the local filesystem via crafted zip entry names containing path traversal sequences. This could allow the third party to perform inappropriate actions in the diagram bundle.
To remediate this issue, users should upgrade to the version 0.24 or later.
{
"affected": [],
"aliases": [
"CVE-2026-81838"
],
"database_specific": {
"cwe_ids": [
"CWE-23"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-27T20:18:56Z",
"severity": "MODERATE"
},
"details": "A relative path traversal issue in the zip extraction functionality in AWS diagram-as-code (awsdac) in versions 0.10 through 0.23 can allow a third party to write arbitrary files to the local filesystem via crafted zip entry names containing path traversal sequences. This could allow the third party to perform inappropriate actions in the diagram bundle.\n\n\n\nTo remediate this issue, users should upgrade to the version 0.24 or later.",
"id": "GHSA-5w99-758f-6jvm",
"modified": "2026-08-27T21:31:54Z",
"published": "2026-08-27T21:31:54Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-81838"
},
{
"type": "WEB",
"url": "https://aws.amazon.com/security/security-bulletins/2026-090-aws"
},
{
"type": "WEB",
"url": "https://github.com/awslabs/diagram-as-code/releases/tag/v0.24"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:H/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-5WCV-J62R-8FP5
Vulnerability from github – Published: 2026-07-28 12:31 – Updated: 2026-07-28 12:31A Path Traversal vulnerability exists in Quick.CMS through the URI path component of HTTP requests, where the server fails to normalize dot-dot-slash (../) sequences before resolving and serving the requested file. An authenticated attacker with admin privileges can use this vulnerability to read contents of files located in the sibling directory of the webroot via a crafted HTTP request containing ../ sequences in the URI.
The vendor assessed the likelihood of exploitation as very low and determined that a fix is not necessary.
{
"affected": [],
"aliases": [
"CVE-2026-63303"
],
"database_specific": {
"cwe_ids": [
"CWE-23"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-28T11:17:04Z",
"severity": "MODERATE"
},
"details": "A Path Traversal vulnerability exists in Quick.CMS through the URI path component of HTTP requests, where the server fails to normalize dot-dot-slash (../) sequences before resolving and serving the requested file. An authenticated attacker with admin privileges\u00a0can use this vulnerability to read contents of files located in the sibling directory of the webroot via a crafted HTTP request containing ../ sequences in the URI.\n\n\nThe vendor assessed the likelihood of exploitation as very low and determined that a fix is\u00a0not necessary.",
"id": "GHSA-5wcv-j62r-8fp5",
"modified": "2026-07-28T12:31:21Z",
"published": "2026-07-28T12:31:21Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-63303"
},
{
"type": "WEB",
"url": "https://cert.pl/en/posts/2026/07/CVE-2026-63301"
},
{
"type": "WEB",
"url": "https://opensolution.org"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:N/SC:L/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-5XG3-J2J6-RCX4
Vulnerability from github – Published: 2021-08-25 21:01 – Updated: 2021-09-09 16:46git-delta before 0.8.3 on Windows resolves an executable's pathname as a relative path from the current directory.
{
"affected": [
{
"package": {
"ecosystem": "crates.io",
"name": "git-delta"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.8.3"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2021-36376"
],
"database_specific": {
"cwe_ids": [
"CWE-23",
"CWE-427"
],
"github_reviewed": true,
"github_reviewed_at": "2021-07-14T19:06:14Z",
"nvd_published_at": "2021-07-13T13:15:00Z",
"severity": "HIGH"
},
"details": "git-delta before 0.8.3 on Windows resolves an executable\u0027s pathname as a relative path from the current directory.",
"id": "GHSA-5xg3-j2j6-rcx4",
"modified": "2021-09-09T16:46:42Z",
"published": "2021-08-25T21:01:39Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-36376"
},
{
"type": "WEB",
"url": "https://github.com/dandavison/delta/commit/f01846bd443aaf92fdd5ac20f461beac3f6ee3fd"
},
{
"type": "PACKAGE",
"url": "https://github.com/dandavison/delta"
},
{
"type": "WEB",
"url": "https://github.com/dandavison/delta/releases/tag/0.8.3"
},
{
"type": "WEB",
"url": "https://rustsec.org/advisories/RUSTSEC-2021-0105.html"
},
{
"type": "WEB",
"url": "https://vuln.ryotak.me/advisories/54"
}
],
"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:H",
"type": "CVSS_V3"
}
],
"summary": "Relative Path Traversal in git-delta"
}
GHSA-62V5-4XC7-QM62
Vulnerability from github – Published: 2026-07-03 21:31 – Updated: 2026-07-03 21:31Relative path traversal in Microsoft Edge (Chromium-based) allows an unauthorized attacker to execute code over a network.
{
"affected": [],
"aliases": [
"CVE-2026-57988"
],
"database_specific": {
"cwe_ids": [
"CWE-23"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-03T21:17:02Z",
"severity": "HIGH"
},
"details": "Relative path traversal in Microsoft Edge (Chromium-based) allows an unauthorized attacker to execute code over a network.",
"id": "GHSA-62v5-4xc7-qm62",
"modified": "2026-07-03T21:31:39Z",
"published": "2026-07-03T21:31:39Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-57988"
},
{
"type": "WEB",
"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-57988"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:L",
"type": "CVSS_V3"
}
]
}
GHSA-63P8-63FF-XR65
Vulnerability from github – Published: 2022-05-24 22:01 – Updated: 2022-07-03 00:00bblfshd is an open source self-hosted server for source code parsing. In bblfshd before commit 4265465b9b6fb5663c30ee43806126012066aad4 there is a "zipslip" vulnerability. The unsafe handling of symbolic links in an unpacking routine may enable attackers to read and/or write to arbitrary locations outside the designated target folder. This issue may lead to arbitrary file write (with same permissions as the program running the unpack operation) if the attacker can control the archive file. Additionally, if the attacker has read access to the unpacked files, he may be able to read arbitrary system files the parent process has permissions to read. For more details including a PoC see the referenced GHSL-2020-258.
{
"affected": [],
"aliases": [
"CVE-2021-32825"
],
"database_specific": {
"cwe_ids": [
"CWE-22",
"CWE-23",
"CWE-59"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2021-08-16T19:15:00Z",
"severity": "CRITICAL"
},
"details": "bblfshd is an open source self-hosted server for source code parsing. In bblfshd before commit 4265465b9b6fb5663c30ee43806126012066aad4 there is a \"zipslip\" vulnerability. The unsafe handling of symbolic links in an unpacking routine may enable attackers to read and/or write to arbitrary locations outside the designated target folder. This issue may lead to arbitrary file write (with same permissions as the program running the unpack operation) if the attacker can control the archive file. Additionally, if the attacker has read access to the unpacked files, he may be able to read arbitrary system files the parent process has permissions to read. For more details including a PoC see the referenced GHSL-2020-258.",
"id": "GHSA-63p8-63ff-xr65",
"modified": "2022-07-03T00:00:24Z",
"published": "2022-05-24T22:01:43Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-32825"
},
{
"type": "WEB",
"url": "https://github.com/bblfsh/bblfshd/pull/341"
},
{
"type": "WEB",
"url": "https://github.com/bblfsh/bblfshd/commit/4265465b9b6fb5663c30ee43806126012066aad4"
},
{
"type": "PACKAGE",
"url": "https://github.com/bblfsh/bblfshd"
},
{
"type": "ADVISORY",
"url": "https://securitylab.github.com/advisories/GHSL-2020-258-zipslip-bblfshd"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
"type": "CVSS_V3"
}
],
"summary": "ZipSlip vulnerability in bblfshd"
}
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-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-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].
CAPEC-139: Relative Path Traversal
An attacker exploits a weakness in input validation on the target by supplying a specially constructed path utilizing dot and slash characters for the purpose of obtaining access to arbitrary files or resources. An attacker modifies a known path on the target in order to reach material that is not available through intended channels. These attacks normally involve adding additional path separators (/ or \) and/or dots (.), or encodings thereof, in various combinations in order to reach parent directories or entirely separate trees of the target's directory structure.
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.