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.
13258 vulnerabilities reference this CWE, most recent first.
GHSA-2237-FVGV-WPG8
Vulnerability from github – Published: 2022-05-17 03:56 – Updated: 2022-05-17 03:56Directory traversal vulnerability in the dotTailLogServlet in dotCMS before 3.5.1 allows remote authenticated administrators to read arbitrary files via a .. (dot dot) in the fileName parameter.
{
"affected": [],
"aliases": [
"CVE-2016-3972"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2016-04-18T15:59:00Z",
"severity": "MODERATE"
},
"details": "Directory traversal vulnerability in the dotTailLogServlet in dotCMS before 3.5.1 allows remote authenticated administrators to read arbitrary files via a .. (dot dot) in the fileName parameter.",
"id": "GHSA-2237-fvgv-wpg8",
"modified": "2022-05-17T03:56:54Z",
"published": "2022-05-17T03:56:54Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2016-3972"
},
{
"type": "WEB",
"url": "http://dotcms.com/security/SI-34"
},
{
"type": "WEB",
"url": "http://seclists.org/fulldisclosure/2016/Apr/36"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-2238-XC5R-V9HJ
Vulnerability from github – Published: 2026-03-12 17:50 – Updated: 2026-03-12 19:13Description
TinaCMS allows users to create, update, and delete content documents using relative file paths (relativePath, newRelativePath) via GraphQL mutations. Under certain conditions, these paths are combined with the collection path using path.join() without validating that the resolved path remains within the collection root directory.
Because path.join() does not prevent directory traversal, paths containing ../ sequences can escape the intended directory boundary.
Attack Vectors
-
File Creation: Create files outside the collection directory
graphql createDocument( collection: "post" relativePath: "../../config/malicious.md" params: { post: { title: "malicious" } } ) -
File Move/Rename: Move existing files outside the collection
graphql updateDocument( collection: "post" relativePath: "existing.md" params: { relativePath: "../../stolen.md" } ) -
File Deletion: Delete files outside the collection
graphql deleteDocument( collection: "post" relativePath: "../../important-config.md" ) -
Folder Creation: Create folders outside the collection
graphql createFolder( collection: "post" relativePath: "../../malicious-folder" )
Impact
An authenticated user with document mutation permissions can:
- Create content files outside collection boundaries (subject to schema validation)
- Move or rename files outside collection boundaries
- Delete content files outside collection boundaries
- Read file contents via document retrieval mutations
Mitigating Factors
Several constraints limit the practical impact of this vulnerability:
-
Schema Validation: Created/updated content must conform to the collection's GraphQL schema. Attackers cannot write arbitrary file content—the
paramsargument is validated against the generated mutation types (e.g.,PostMutation). -
Authentication Required: Exploitation requires authenticated access with CMS editor permissions. Anonymous users cannot access GraphQL mutations.
-
Git Tracking: In typical deployments, all file operations are tracked in git (either via GitHub API for Tina Cloud/self-hosted with GitProvider, or local filesystem changes). Malicious changes are visible in version control and can be reverted.
What This Vulnerability Does NOT Allow
- Writing arbitrary file content (content is schema-validated)
- Silent/untracked file modifications (changes appear in git)
- Unauthenticated access
Proof of Concept
See packages/@tinacms/graphql/tests/path-traversal-security/index.test.ts for automated tests demonstrating the vulnerability.
Manual reproduction:
node -e "
const path = require('path');
const collectionPath = 'content/posts';
const maliciousRelativePath = '../../OUTSIDE/poc.md';
const realPath = path.join(collectionPath, maliciousRelativePath);
console.log('Resolved path:', realPath);
// Output: OUTSIDE/poc.md (escaped content/posts)
"
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 2.1.1"
},
"package": {
"ecosystem": "npm",
"name": "@tinacms/graphql"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2.1.2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-24125"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": true,
"github_reviewed_at": "2026-03-12T17:50:28Z",
"nvd_published_at": "2026-03-12T17:16:39Z",
"severity": "MODERATE"
},
"details": "### Description\n\nTinaCMS allows users to create, update, and delete content documents using relative file paths (`relativePath`, `newRelativePath`) via GraphQL mutations. Under certain conditions, these paths are combined with the collection path using `path.join()` without validating that the resolved path remains within the collection root directory.\n\nBecause `path.join()` does not prevent directory traversal, paths containing `../` sequences can escape the intended directory boundary.\n\n### Attack Vectors\n\n1. **File Creation**: Create files outside the collection directory\n ```graphql\n createDocument(\n collection: \"post\"\n relativePath: \"../../config/malicious.md\"\n params: { post: { title: \"malicious\" } }\n )\n ```\n\n2. **File Move/Rename**: Move existing files outside the collection\n ```graphql\n updateDocument(\n collection: \"post\"\n relativePath: \"existing.md\"\n params: { relativePath: \"../../stolen.md\" }\n )\n ```\n\n3. **File Deletion**: Delete files outside the collection\n ```graphql\n deleteDocument(\n collection: \"post\"\n relativePath: \"../../important-config.md\"\n )\n ```\n\n4. **Folder Creation**: Create folders outside the collection\n ```graphql\n createFolder(\n collection: \"post\"\n relativePath: \"../../malicious-folder\"\n )\n ```\n\n## Impact\n\nAn authenticated user with document mutation permissions can:\n\n- **Create content files** outside collection boundaries (subject to schema validation)\n- **Move or rename files** outside collection boundaries\n- **Delete content files** outside collection boundaries\n- **Read file contents** via document retrieval mutations\n\n## Mitigating Factors\n\nSeveral constraints limit the practical impact of this vulnerability:\n\n1. **Schema Validation**: Created/updated content must conform to the collection\u0027s GraphQL schema. Attackers cannot write arbitrary file content\u2014the `params` argument is validated against the generated mutation types (e.g., `PostMutation`).\n\n2. **Authentication Required**: Exploitation requires authenticated access with CMS editor permissions. Anonymous users cannot access GraphQL mutations.\n\n3. **Git Tracking**: In typical deployments, all file operations are tracked in git (either via GitHub API for Tina Cloud/self-hosted with GitProvider, or local filesystem changes). Malicious changes are visible in version control and can be reverted.\n\n### What This Vulnerability Does NOT Allow\n\n- Writing arbitrary file content (content is schema-validated)\n- Silent/untracked file modifications (changes appear in git)\n- Unauthenticated access\n\n## Proof of Concept\n\nSee `packages/@tinacms/graphql/tests/path-traversal-security/index.test.ts` for automated tests demonstrating the vulnerability.\n\nManual reproduction:\n```bash\nnode -e \"\nconst path = require(\u0027path\u0027);\n\nconst collectionPath = \u0027content/posts\u0027;\nconst maliciousRelativePath = \u0027../../OUTSIDE/poc.md\u0027;\n\nconst realPath = path.join(collectionPath, maliciousRelativePath);\nconsole.log(\u0027Resolved path:\u0027, realPath);\n// Output: OUTSIDE/poc.md (escaped content/posts)\n\"\n```",
"id": "GHSA-2238-xc5r-v9hj",
"modified": "2026-03-12T19:13:56Z",
"published": "2026-03-12T17:50:28Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/tinacms/tinacms/security/advisories/GHSA-2238-xc5r-v9hj"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-24125"
},
{
"type": "PACKAGE",
"url": "https://github.com/tinacms/tinacms"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L",
"type": "CVSS_V3"
}
],
"summary": "@tinacms/graphql has a Path Traversal issue"
}
GHSA-224H-P7P5-RH85
Vulnerability from github – Published: 2020-09-01 17:32 – Updated: 2021-09-23 21:43Affected versions of wenluhong1 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
No patch is available for this vulnerability.
It is recommended that the package is only used for local development, and if the functionality is needed for production, a different package is used instead.
{
"affected": [
{
"package": {
"ecosystem": "npm",
"name": "wenluhong1"
},
"ranges": [
{
"events": [
{
"introduced": "0.0.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": true,
"github_reviewed_at": "2020-08-31T18:22:00Z",
"nvd_published_at": null,
"severity": "HIGH"
},
"details": "Affected versions of `wenluhong1` 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\nExample request:\n```\nGET /../../../../../../../../../../etc/passwd HTTP/1.1\nhost:foo\n```\n\n\n## Recommendation\n\nNo patch is available for this vulnerability.\n\nIt is recommended that the package is only used for local development, and if the functionality is needed for production, a different package is used instead.",
"id": "GHSA-224h-p7p5-rh85",
"modified": "2021-09-23T21:43:28Z",
"published": "2020-09-01T17:32:26Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/JacksonGL/NPM-Vuln-PoC/blob/master/directory-traversal/wenluhong1"
},
{
"type": "WEB",
"url": "https://snyk.io/vuln/npm:wenluhong1:20170509"
},
{
"type": "WEB",
"url": "https://www.npmjs.com/advisories/409"
}
],
"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"
}
],
"summary": "Directory Traversal in wenluhong1"
}
GHSA-2256-F5J7-R5HQ
Vulnerability from github – Published: 2024-05-16 18:30 – Updated: 2024-05-16 18:30Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in Samuel Marshall JCH Optimize.This issue affects JCH Optimize: from n/a through 4.2.0.
{
"affected": [],
"aliases": [
"CVE-2024-34808"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-05-16T16:15:09Z",
"severity": "MODERATE"
},
"details": "Improper Limitation of a Pathname to a Restricted Directory (\u0027Path Traversal\u0027) vulnerability in Samuel Marshall JCH Optimize.This issue affects JCH Optimize: from n/a through 4.2.0.",
"id": "GHSA-2256-f5j7-r5hq",
"modified": "2024-05-16T18:30:32Z",
"published": "2024-05-16T18:30:32Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-34808"
},
{
"type": "WEB",
"url": "https://patchstack.com/database/vulnerability/jch-optimize/wordpress-jch-optimize-plugin-4-2-0-path-traversal-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:L/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-225J-RC3H-9R34
Vulnerability from github – Published: 2022-05-24 19:05 – Updated: 2022-05-24 19:05Sonatype Nexus Repository Manager 3.x before 3.31.0 allows a remote authenticated attacker to get a list of blob files and read the content of a blob file (via a GET request) without having been granted access.
{
"affected": [],
"aliases": [
"CVE-2021-34553"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2021-06-18T00:15:00Z",
"severity": "MODERATE"
},
"details": "Sonatype Nexus Repository Manager 3.x before 3.31.0 allows a remote authenticated attacker to get a list of blob files and read the content of a blob file (via a GET request) without having been granted access.",
"id": "GHSA-225j-rc3h-9r34",
"modified": "2022-05-24T19:05:41Z",
"published": "2022-05-24T19:05:41Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-34553"
},
{
"type": "WEB",
"url": "https://support.sonatype.com/hc/en-us/articles/4402433828371"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-225X-44W7-HH2F
Vulnerability from github – Published: 2024-04-05 18:30 – Updated: 2024-04-05 18:30A path traversal vulnerability exists in the Java version of CData Sync < 23.4.8843 when running using the embedded Jetty server, which could allow an unauthenticated remote attacker to gain access to sensitive information and perform limited actions.
{
"affected": [],
"aliases": [
"CVE-2024-31851"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-04-05T18:15:09Z",
"severity": "HIGH"
},
"details": "A path traversal vulnerability exists in the Java version of CData Sync \u003c 23.4.8843 when running using the embedded Jetty server, which could allow an unauthenticated remote attacker to gain access to sensitive information and perform limited actions.",
"id": "GHSA-225x-44w7-hh2f",
"modified": "2024-04-05T18:30:35Z",
"published": "2024-04-05T18:30:35Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-31851"
},
{
"type": "WEB",
"url": "https://www.tenable.com/security/research/tra-2024-09"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L",
"type": "CVSS_V3"
}
]
}
GHSA-227R-W5J2-6243
Vulnerability from github – Published: 2025-03-20 12:32 – Updated: 2025-03-21 16:32In invoke-ai/invokeai version v5.0.2, the web API POST /api/v1/images/delete is vulnerable to Arbitrary File Deletion. This vulnerability allows unauthorized attackers to delete arbitrary files on the server, potentially including critical or sensitive system files such as SSH keys, SQLite databases, and configuration files. This can impact the integrity and availability of applications relying on these files.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "InvokeAI"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "5.3.0rc1"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2024-11042"
],
"database_specific": {
"cwe_ids": [
"CWE-20",
"CWE-22",
"CWE-73"
],
"github_reviewed": true,
"github_reviewed_at": "2025-03-21T16:32:50Z",
"nvd_published_at": "2025-03-20T10:15:23Z",
"severity": "CRITICAL"
},
"details": "In invoke-ai/invokeai version v5.0.2, the web API `POST /api/v1/images/delete` is vulnerable to Arbitrary File Deletion. This vulnerability allows unauthorized attackers to delete arbitrary files on the server, potentially including critical or sensitive system files such as SSH keys, SQLite databases, and configuration files. This can impact the integrity and availability of applications relying on these files.",
"id": "GHSA-227r-w5j2-6243",
"modified": "2025-03-21T16:32:50Z",
"published": "2025-03-20T12:32:41Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-11042"
},
{
"type": "WEB",
"url": "https://github.com/invoke-ai/invokeai/commit/5440c037674882b2ab7acd59087e9bb04b49657a"
},
{
"type": "PACKAGE",
"url": "https://github.com/invoke-ai/InvokeAI"
},
{
"type": "WEB",
"url": "https://huntr.com/bounties/635535a7-c804-4789-ac3a-48d951263987"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H",
"type": "CVSS_V3"
}
],
"summary": "InvokeAI Arbitrary File Deletion vulnerability"
}
GHSA-227V-M6P6-J6GX
Vulnerability from github – Published: 2023-11-03 18:30 – Updated: 2023-11-03 18:30A path traversal vulnerability has been reported to affect Music Station. If exploited, the vulnerability could allow users to read the contents of unexpected files and expose sensitive data via a network.
We have already fixed the vulnerability in the following versions: Music Station 4.8.11 and later Music Station 5.1.16 and later Music Station 5.3.23 and later
{
"affected": [],
"aliases": [
"CVE-2023-39299"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-11-03T17:15:08Z",
"severity": "HIGH"
},
"details": "A path traversal vulnerability has been reported to affect Music Station. If exploited, the vulnerability could allow users to read the contents of unexpected files and expose sensitive data via a network.\n\nWe have already fixed the vulnerability in the following versions:\nMusic Station 4.8.11 and later\nMusic Station 5.1.16 and later\nMusic Station 5.3.23 and later\n",
"id": "GHSA-227v-m6p6-j6gx",
"modified": "2023-11-03T18:30:24Z",
"published": "2023-11-03T18:30:24Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-39299"
},
{
"type": "WEB",
"url": "https://www.qnap.com/en/security-advisory/qsa-23-61"
}
],
"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"
}
]
}
GHSA-2284-5WV4-383M
Vulnerability from github – Published: 2022-05-01 18:26 – Updated: 2022-05-01 18:26Directory traversal vulnerability in Web Oddity 0.09b allows remote attackers to read arbitrary files via a .. (dot dot) in the URI.
{
"affected": [],
"aliases": [
"CVE-2007-4726"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2007-09-05T19:17:00Z",
"severity": "MODERATE"
},
"details": "Directory traversal vulnerability in Web Oddity 0.09b allows remote attackers to read arbitrary files via a .. (dot dot) in the URI.",
"id": "GHSA-2284-5wv4-383m",
"modified": "2022-05-01T18:26:31Z",
"published": "2022-05-01T18:26:31Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2007-4726"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/36427"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/exploits/4362"
},
{
"type": "WEB",
"url": "http://osvdb.org/41028"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/25535"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-2284-8CW5-5697
Vulnerability from github – Published: 2026-04-05 21:30 – Updated: 2026-04-05 21:30Pegasus CMS 1.0 contains a remote code execution vulnerability in the extra_fields.php plugin that allows unauthenticated attackers to execute arbitrary commands by exploiting unsafe eval functionality. Attackers can send POST requests to the submit.php endpoint with malicious PHP code in the action parameter to achieve code execution and obtain an interactive shell.
{
"affected": [],
"aliases": [
"CVE-2019-25687"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-04-05T21:16:47Z",
"severity": "CRITICAL"
},
"details": "Pegasus CMS 1.0 contains a remote code execution vulnerability in the extra_fields.php plugin that allows unauthenticated attackers to execute arbitrary commands by exploiting unsafe eval functionality. Attackers can send POST requests to the submit.php endpoint with malicious PHP code in the action parameter to achieve code execution and obtain an interactive shell.",
"id": "GHSA-2284-8cw5-5697",
"modified": "2026-04-05T21:30:21Z",
"published": "2026-04-05T21:30:21Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2019-25687"
},
{
"type": "WEB",
"url": "https://www.exploit-db.com/exploits/46542"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/pegasus-cms-remote-code-execution-via-extra-fields-php"
},
{
"type": "WEB",
"url": "https://www.wisdom.com.au/web/pegasus-cms"
}
],
"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"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/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"
}
]
}
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.