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.
13197 vulnerabilities reference this CWE, most recent first.
GHSA-23GM-HJPG-QFP3
Vulnerability from github – Published: 2022-05-24 16:58 – Updated: 2024-04-04 02:29ThinVNC 1.0b1 is vulnerable to arbitrary file read, which leads to a compromise of the VNC server. The vulnerability exists even when authentication is turned on during the deployment of the VNC server. The password for authentication is stored in cleartext in a file that can be read via a ../../ThinVnc.ini directory traversal attack vector.
{
"affected": [],
"aliases": [
"CVE-2019-17662"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2019-10-16T18:15:00Z",
"severity": "CRITICAL"
},
"details": "ThinVNC 1.0b1 is vulnerable to arbitrary file read, which leads to a compromise of the VNC server. The vulnerability exists even when authentication is turned on during the deployment of the VNC server. The password for authentication is stored in cleartext in a file that can be read via a ../../ThinVnc.ini directory traversal attack vector.",
"id": "GHSA-23gm-hjpg-qfp3",
"modified": "2024-04-04T02:29:05Z",
"published": "2022-05-24T16:58:57Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-17662"
},
{
"type": "WEB",
"url": "https://github.com/bewest/thinvnc/issues/5"
},
{
"type": "WEB",
"url": "https://github.com/shashankmangal2/Exploits/blob/master/ThinVNC-RemoteAccess/POC.py"
},
{
"type": "WEB",
"url": "https://redteamzone.com/ThinVNC"
},
{
"type": "WEB",
"url": "http://packetstormsecurity.com/files/154896/ThinVNC-1.0b1-Authentication-Bypass.html"
}
],
"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:H",
"type": "CVSS_V3"
}
]
}
GHSA-23H5-8PH6-7RFC
Vulnerability from github – Published: 2022-02-16 00:01 – Updated: 2023-10-27 16:24Jenkins Fortify Plugin 20.2.34 and earlier does not sanitize the appName and appVersion parameters of its Pipeline steps, which are used to write to files inside build directories.
This allows attackers with Item/Configure permission to write or overwrite .xml files on the Jenkins controller file system with content not controllable by the attacker.
Jenkins Fortify Plugin 20.2.35 sanitizes the appName and appVersion parameters of its Pipeline steps when determining the resulting filename.
{
"affected": [
{
"package": {
"ecosystem": "Maven",
"name": "org.jenkins-ci.plugins:fortify"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "20.2.35"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2022-25188"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": true,
"github_reviewed_at": "2022-12-01T23:05:05Z",
"nvd_published_at": "2022-02-15T17:15:00Z",
"severity": "MODERATE"
},
"details": "Jenkins Fortify Plugin 20.2.34 and earlier does not sanitize the `appName` and `appVersion` parameters of its Pipeline steps, which are used to write to files inside build directories.\n\nThis allows attackers with Item/Configure permission to write or overwrite `.xml` files on the Jenkins controller file system with content not controllable by the attacker.\n\nJenkins Fortify Plugin 20.2.35 sanitizes the `appName` and `appVersion` parameters of its Pipeline steps when determining the resulting filename.",
"id": "GHSA-23h5-8ph6-7rfc",
"modified": "2023-10-27T16:24:32Z",
"published": "2022-02-16T00:01:27Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-25188"
},
{
"type": "WEB",
"url": "https://github.com/jenkinsci/fortify-plugin/commit/ba3030cb63bb86b6bb13342664e0e319f2fee374"
},
{
"type": "PACKAGE",
"url": "https://github.com/jenkinsci/fortify-plugin"
},
{
"type": "WEB",
"url": "https://www.jenkins.io/security/advisory/2022-02-15/#SECURITY-2214"
},
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2022/02/15/2"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "Path traversal vulnerability in Jenkins Fortify Plugin"
}
GHSA-23HC-GF5P-JQ23
Vulnerability from github – Published: 2025-10-22 15:31 – Updated: 2026-01-20 15:31Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in AmentoTech Workreap (theme's plugin) workreap allows Path Traversal.This issue affects Workreap (theme's plugin): from n/a through <= 3.3.5.
{
"affected": [],
"aliases": [
"CVE-2025-59566"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-10-22T15:15:55Z",
"severity": "HIGH"
},
"details": "Improper Limitation of a Pathname to a Restricted Directory (\u0027Path Traversal\u0027) vulnerability in AmentoTech Workreap (theme\u0027s plugin) workreap allows Path Traversal.This issue affects Workreap (theme\u0027s plugin): from n/a through \u003c= 3.3.5.",
"id": "GHSA-23hc-gf5p-jq23",
"modified": "2026-01-20T15:31:29Z",
"published": "2025-10-22T15:31:17Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-59566"
},
{
"type": "WEB",
"url": "https://patchstack.com/database/Wordpress/Plugin/workreap/vulnerability/wordpress-workreap-theme-s-plugin-plugin-3-3-5-arbitrary-file-deletion-vulnerability?_s_id=cve"
},
{
"type": "WEB",
"url": "https://vdp.patchstack.com/database/Wordpress/Plugin/workreap/vulnerability/wordpress-workreap-theme-s-plugin-plugin-3-3-5-arbitrary-file-deletion-vulnerability"
},
{
"type": "WEB",
"url": "https://vdp.patchstack.com/database/Wordpress/Plugin/workreap/vulnerability/wordpress-workreap-theme-s-plugin-plugin-3-3-5-arbitrary-file-deletion-vulnerability?_s_id=cve"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:L",
"type": "CVSS_V3"
}
]
}
GHSA-23HH-7W49-JRPV
Vulnerability from github – Published: 2025-11-14 21:30 – Updated: 2025-11-14 21:30A security vulnerability has been detected in SimStudioAI sim up to ed9b9ad83f1a7c61f4392787fb51837d34eeb0af. This affects an unknown part. The manipulation of the argument filePath leads to path traversal. Remote exploitation of the attack is possible. The exploit has been disclosed publicly and may be used. This product follows a rolling release approach for continuous delivery, so version details for affected or updated releases are not provided. The identifier of the patch is 45372aece5e05e04b417442417416a52e90ba174. To fix this issue, it is recommended to deploy a patch.
{
"affected": [],
"aliases": [
"CVE-2025-9801"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-09-01T23:15:29Z",
"severity": "MODERATE"
},
"details": "A security vulnerability has been detected in SimStudioAI sim up to ed9b9ad83f1a7c61f4392787fb51837d34eeb0af. This affects an unknown part. The manipulation of the argument filePath leads to path traversal. Remote exploitation of the attack is possible. The exploit has been disclosed publicly and may be used. This product follows a rolling release approach for continuous delivery, so version details for affected or updated releases are not provided. The identifier of the patch is 45372aece5e05e04b417442417416a52e90ba174. To fix this issue, it is recommended to deploy a patch.",
"id": "GHSA-23hh-7w49-jrpv",
"modified": "2025-11-14T21:30:28Z",
"published": "2025-11-14T21:30:28Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-9801"
},
{
"type": "WEB",
"url": "https://github.com/simstudioai/sim/issues/959"
},
{
"type": "WEB",
"url": "https://github.com/simstudioai/sim/issues/959#issue-3320697951"
},
{
"type": "WEB",
"url": "https://github.com/simstudioai/sim/issues/959#issuecomment-3221311557"
},
{
"type": "WEB",
"url": "https://github.com/simstudioai/sim/commit/45372aece5e05e04b417442417416a52e90ba174"
},
{
"type": "WEB",
"url": "https://vuldb.com/?ctiid.322116"
},
{
"type": "WEB",
"url": "https://vuldb.com/?id.322116"
},
{
"type": "WEB",
"url": "https://vuldb.com/?submit.641130"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:L/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-23HM-6GVP-W3W5
Vulnerability from github – Published: 2026-03-21 18:31 – Updated: 2026-03-21 18:31Green CMS 2.x contains a path traversal vulnerability that allows authenticated attackers to download arbitrary files and directories by injecting directory traversal sequences. Attackers can manipulate the theme_name parameter in the themeexporthandle action or supply base64-encoded file paths to the downfile action to retrieve sensitive files outside intended directories.
{
"affected": [],
"aliases": [
"CVE-2019-25574"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-03-21T16:16:00Z",
"severity": "HIGH"
},
"details": "Green CMS 2.x contains a path traversal vulnerability that allows authenticated attackers to download arbitrary files and directories by injecting directory traversal sequences. Attackers can manipulate the theme_name parameter in the themeexporthandle action or supply base64-encoded file paths to the downfile action to retrieve sensitive files outside intended directories.",
"id": "GHSA-23hm-6gvp-w3w5",
"modified": "2026-03-21T18:31:05Z",
"published": "2026-03-21T18:31:05Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-25574"
},
{
"type": "WEB",
"url": "https://codeload.github.com/GreenCMS/GreenCMS/zip/beta"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/exploits/46245"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/green-cms-2-x-path-traversal-arbitrary-file-download"
},
{
"type": "WEB",
"url": "http://www.greencms.net"
}
],
"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-23P4-5PPC-536P
Vulnerability from github – Published: 2022-02-17 00:00 – Updated: 2022-02-26 00:01Forms generated by JQueryForm.com before 2022-02-05 allow remote attackers to obtain the URI to any uploaded file by capturing the POST response. When chained with CVE-2022-24984, this could lead to unauthenticated remote code execution on the underlying web server. This occurs because the Unique ID field is contained in the POST response upon submitting a form.
{
"affected": [],
"aliases": [
"CVE-2022-24983"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-02-16T22:15:00Z",
"severity": "HIGH"
},
"details": "Forms generated by JQueryForm.com before 2022-02-05 allow remote attackers to obtain the URI to any uploaded file by capturing the POST response. When chained with CVE-2022-24984, this could lead to unauthenticated remote code execution on the underlying web server. This occurs because the Unique ID field is contained in the POST response upon submitting a form.",
"id": "GHSA-23p4-5ppc-536p",
"modified": "2022-02-26T00:01:01Z",
"published": "2022-02-17T00:00:26Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-24983"
},
{
"type": "WEB",
"url": "https://JQueryForm.com"
},
{
"type": "WEB",
"url": "https://gist.github.com/pb-nsi/4d0a1ede76d4e97083b3435f820bf560"
},
{
"type": "WEB",
"url": "https://www.nou-systems.com/cyber-security"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-23QV-956X-W2HR
Vulnerability from github – Published: 2022-05-17 02:00 – Updated: 2022-05-17 02:00Directory traversal vulnerability in Best Practical Solutions RT 3.2.0 through 3.6.10, 3.8.0 through 3.8.9, and 4.0.0rc through 4.0.0rc7 allows remote attackers to read arbitrary files via a crafted HTTP request.
{
"affected": [],
"aliases": [
"CVE-2011-1688"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2011-04-22T10:55:00Z",
"severity": "MODERATE"
},
"details": "Directory traversal vulnerability in Best Practical Solutions RT 3.2.0 through 3.6.10, 3.8.0 through 3.8.9, and 4.0.0rc through 4.0.0rc7 allows remote attackers to read arbitrary files via a crafted HTTP request.",
"id": "GHSA-23qv-956x-w2hr",
"modified": "2022-05-17T02:00:08Z",
"published": "2022-05-17T02:00:08Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2011-1688"
},
{
"type": "WEB",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=696795"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/66795"
},
{
"type": "WEB",
"url": "http://blog.bestpractical.com/2011/04/security-vulnerabilities-in-rt.html"
},
{
"type": "WEB",
"url": "http://lists.bestpractical.com/pipermail/rt-announce/2011-April/000187.html"
},
{
"type": "WEB",
"url": "http://lists.bestpractical.com/pipermail/rt-announce/2011-April/000188.html"
},
{
"type": "WEB",
"url": "http://lists.bestpractical.com/pipermail/rt-announce/2011-April/000189.html"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/44189"
},
{
"type": "WEB",
"url": "http://www.debian.org/security/2011/dsa-2220"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/47383"
},
{
"type": "WEB",
"url": "http://www.vupen.com/english/advisories/2011/1071"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-23RG-JPW2-P6R8
Vulnerability from github – Published: 2023-08-06 00:30 – Updated: 2023-08-06 00:30A vulnerability, which was classified as problematic, has been found in Chengdu Flash Flood Disaster Monitoring and Warning System 2.0. This issue affects some unknown processing of the file \Service\FileHandler.ashx. The manipulation of the argument FileDirectory leads to absolute path traversal. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used. The associated identifier of this vulnerability is VDB-236207.
{
"affected": [],
"aliases": [
"CVE-2023-4172"
],
"database_specific": {
"cwe_ids": [
"CWE-22",
"CWE-36"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-08-05T23:15:13Z",
"severity": "MODERATE"
},
"details": "A vulnerability, which was classified as problematic, has been found in Chengdu Flash Flood Disaster Monitoring and Warning System 2.0. This issue affects some unknown processing of the file \\Service\\FileHandler.ashx. The manipulation of the argument FileDirectory leads to absolute path traversal. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used. The associated identifier of this vulnerability is VDB-236207.",
"id": "GHSA-23rg-jpw2-p6r8",
"modified": "2023-08-06T00:30:17Z",
"published": "2023-08-06T00:30:17Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-4172"
},
{
"type": "WEB",
"url": "https://github.com/nagenanhai/cve/blob/main/duqu2.md"
},
{
"type": "WEB",
"url": "https://vuldb.com/?ctiid.236207"
},
{
"type": "WEB",
"url": "https://vuldb.com/?id.236207"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-23V6-MXRM-P953
Vulnerability from github – Published: 2022-05-14 02:41 – Updated: 2022-05-14 02:41Directory traversal vulnerability in the web server in Philips Electronics VOIP841 DECT Phone with firmware 1.0.4.50 and 1.0.4.80 allows remote authenticated users to read arbitrary files via a .. (dot dot) in a GET request. NOTE: this can be leveraged with CVE-2008-4874 for unauthenticated access to sensitive files such as (1) save.dat and (2) apply.log, which can contain other credentials such as the Skype username and password.
{
"affected": [],
"aliases": [
"CVE-2008-4875"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2008-11-01T06:00:00Z",
"severity": "MODERATE"
},
"details": "Directory traversal vulnerability in the web server in Philips Electronics VOIP841 DECT Phone with firmware 1.0.4.50 and 1.0.4.80 allows remote authenticated users to read arbitrary files via a .. (dot dot) in a GET request. NOTE: this can be leveraged with CVE-2008-4874 for unauthenticated access to sensitive files such as (1) save.dat and (2) apply.log, which can contain other credentials such as the Skype username and password.",
"id": "GHSA-23v6-mxrm-p953",
"modified": "2022-05-14T02:41:03Z",
"published": "2022-05-14T02:41:03Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2008-4875"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/40534"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/exploits/5113"
},
{
"type": "WEB",
"url": "http://osvdb.org/42941"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/28978"
},
{
"type": "WEB",
"url": "http://securityreason.com/securityalert/4536"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/archive/1/488127/100/200/threaded"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/27790"
},
{
"type": "WEB",
"url": "http://www.vupen.com/english/advisories/2008/0583"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-23VF-5G53-HM9Q
Vulnerability from github – Published: 2018-07-24 14:57 – Updated: 2023-09-06 20:10Affected versions of list-n-stream resolve relative file paths, resulting in a directory traversal vulnerability. A malicious actor can use this vulnerability to access files outside of the intended directory root, which may result in the disclosure of private files on the vulnerable system.
Example request:
GET /../../../../../../../../../../etc/passwd HTTP/1.1
host:foo
Recommendation
Update to version 0.0.11 or later.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 0.0.10"
},
"package": {
"ecosystem": "npm",
"name": "list-n-stream"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.0.11"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2017-16084"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": true,
"github_reviewed_at": "2020-06-16T20:51:10Z",
"nvd_published_at": null,
"severity": "HIGH"
},
"details": "Affected versions of `list-n-stream` resolve relative file paths, resulting in a directory traversal vulnerability. A malicious actor can use this vulnerability to access files outside of the intended directory root, which may result in the disclosure of private files on the vulnerable system.\n\n**Example request:**\n```http\nGET /../../../../../../../../../../etc/passwd HTTP/1.1\nhost:foo\n```\n\n\n## Recommendation\n\nUpdate to version 0.0.11 or later.",
"id": "GHSA-23vf-5g53-hm9q",
"modified": "2023-09-06T20:10:43Z",
"published": "2018-07-24T14:57:31Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2017-16084"
},
{
"type": "WEB",
"url": "https://github.com/JacksonGL/NPM-Vuln-PoC/tree/master/directory-traversal/list-n-stream"
},
{
"type": "ADVISORY",
"url": "https://github.com/advisories/GHSA-23vf-5g53-hm9q"
},
{
"type": "WEB",
"url": "https://www.npmjs.com/advisories/344"
}
],
"schema_version": "1.4.0",
"severity": [],
"summary": "Directory Traversal in list-n-stream"
}
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.