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.
13025 vulnerabilities reference this CWE, most recent first.
GHSA-C2FX-6QC9-26X9
Vulnerability from github – Published: 2023-11-21 15:30 – Updated: 2023-11-28 21:30Relative URLs starting with three slashes were incorrectly parsed, and a path-traversal "/../" part in the path could be used to override the specified host. This could contribute to security problems in web sites. This vulnerability affects Firefox < 120, Firefox < 115.5, and Thunderbird < 115.5.0.
{
"affected": [],
"aliases": [
"CVE-2023-6209"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-11-21T15:15:07Z",
"severity": "MODERATE"
},
"details": "Relative URLs starting with three slashes were incorrectly parsed, and a path-traversal \"/../\" part in the path could be used to override the specified host. This could contribute to security problems in web sites. This vulnerability affects Firefox \u003c 120, Firefox \u003c 115.5, and Thunderbird \u003c 115.5.0.",
"id": "GHSA-c2fx-6qc9-26x9",
"modified": "2023-11-28T21:30:24Z",
"published": "2023-11-21T15:30:20Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-6209"
},
{
"type": "WEB",
"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1858570"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2023/11/msg00017.html"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2023/11/msg00030.html"
},
{
"type": "WEB",
"url": "https://www.debian.org/security/2023/dsa-5561"
},
{
"type": "WEB",
"url": "https://www.mozilla.org/security/advisories/mfsa2023-49"
},
{
"type": "WEB",
"url": "https://www.mozilla.org/security/advisories/mfsa2023-50"
},
{
"type": "WEB",
"url": "https://www.mozilla.org/security/advisories/mfsa2023-52"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-C2H3-6MXW-7MVQ
Vulnerability from github – Published: 2021-10-04 20:14 – Updated: 2021-10-15 17:31Impact
A bug was found in containerd where container root directories and some plugins had insufficiently restricted permissions, allowing otherwise unprivileged Linux users to traverse directory contents and execute programs. When containers included executable programs with extended permission bits (such as setuid), unprivileged Linux users could discover and execute those programs. When the UID of an unprivileged Linux user on the host collided with the file owner or group inside a container, the unprivileged Linux user on the host could discover, read, and modify those files.
Patches
This vulnerability has been fixed in containerd 1.4.11 and containerd 1.5.7. Users should update to these version when they are released and may restart containers or update directory permissions to mitigate the vulnerability.
Workarounds
Limit access to the host to trusted users. Update directory permission on container bundles directories.
For more information
If you have any questions or comments about this advisory: * Open an issue in github.com/containerd/containerd * Email us at security@containerd.io
{
"affected": [
{
"package": {
"ecosystem": "Go",
"name": "github.com/containerd/containerd"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.4.11"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Go",
"name": "github.com/containerd/containerd"
},
"ranges": [
{
"events": [
{
"introduced": "1.5.0"
},
{
"fixed": "1.5.7"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2021-41103"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": true,
"github_reviewed_at": "2021-10-04T17:05:03Z",
"nvd_published_at": "2021-10-04T17:15:00Z",
"severity": "MODERATE"
},
"details": "### Impact\nA bug was found in containerd where container root directories and some plugins had insufficiently restricted permissions, allowing otherwise unprivileged Linux users to traverse directory contents and execute programs. When containers included executable programs with extended permission bits (such as setuid), unprivileged Linux users could discover and execute those programs. When the UID of an unprivileged Linux user on the host collided with the file owner or group inside a container, the unprivileged Linux user on the host could discover, read, and modify those files.\n\n### Patches\nThis vulnerability has been fixed in containerd 1.4.11 and containerd 1.5.7. Users should update to these version when they are released and may restart containers or update directory permissions to mitigate the vulnerability.\n\n### Workarounds\nLimit access to the host to trusted users. Update directory permission on container bundles directories. \n\n### For more information\nIf you have any questions or comments about this advisory: \n* Open an issue in [github.com/containerd/containerd](https://github.com/containerd/containerd/issues/new/choose)\n* Email us at [security@containerd.io](mailto:security@containerd.io)\n",
"id": "GHSA-c2h3-6mxw-7mvq",
"modified": "2021-10-15T17:31:03Z",
"published": "2021-10-04T20:14:47Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/containerd/containerd/security/advisories/GHSA-c2h3-6mxw-7mvq"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-41103"
},
{
"type": "WEB",
"url": "https://github.com/containerd/containerd/commit/5b46e404f6b9f661a205e28d59c982d3634148f8"
},
{
"type": "WEB",
"url": "https://cert-portal.siemens.com/productcert/pdf/ssa-222547.pdf"
},
{
"type": "PACKAGE",
"url": "https://github.com/containerd/containerd"
},
{
"type": "WEB",
"url": "https://github.com/containerd/containerd/releases/tag/v1.4.11"
},
{
"type": "WEB",
"url": "https://github.com/containerd/containerd/releases/tag/v1.5.7"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/B5Q6G6I4W5COQE25QMC7FJY3I3PAYFBB"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZNFADTCHHYWVM6W4NJ6CB4FNFM2VMBIB"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/B5Q6G6I4W5COQE25QMC7FJY3I3PAYFBB"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZNFADTCHHYWVM6W4NJ6CB4FNFM2VMBIB"
},
{
"type": "WEB",
"url": "https://security.gentoo.org/glsa/202401-31"
},
{
"type": "WEB",
"url": "https://www.debian.org/security/2021/dsa-5002"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
"type": "CVSS_V3"
}
],
"summary": "Insufficiently restricted permissions on plugin directories"
}
GHSA-C2H4-63XC-8QH6
Vulnerability from github – Published: 2022-08-16 00:00 – Updated: 2022-08-17 00:00Directory Traversal vulnerability ZDBQAREFSUBDIR parameter in /zropusermgmt API in Zoho ManageEngine Analytics Plus before 4350 allows remote attackers to run arbitrary code.
{
"affected": [],
"aliases": [
"CVE-2020-21642"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-08-15T20:15:00Z",
"severity": "CRITICAL"
},
"details": "Directory Traversal vulnerability ZDBQAREFSUBDIR parameter in /zropusermgmt API in Zoho ManageEngine Analytics Plus before 4350 allows remote attackers to run arbitrary code.",
"id": "GHSA-c2h4-63xc-8qh6",
"modified": "2022-08-17T00:00:23Z",
"published": "2022-08-16T00:00:22Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-21642"
},
{
"type": "WEB",
"url": "https://www.manageengine.com/analytics-plus/release-notes.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-C2P9-CV2V-6744
Vulnerability from github – Published: 2026-06-03 15:30 – Updated: 2026-06-03 15:30An improper limitation of a pathname to a restricted directory ('Path Traversal') vulnerability in Backup Task functionality in Synology Hyper Backup before 4.1.2-4036 allows remote authenticated users to write specific files via unspecified vectors.
{
"affected": [],
"aliases": [
"CVE-2024-47273"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-06-03T14:16:26Z",
"severity": "MODERATE"
},
"details": "An improper limitation of a pathname to a restricted directory (\u0027Path Traversal\u0027) vulnerability in Backup Task functionality in Synology Hyper Backup before 4.1.2-4036 allows remote authenticated users to write specific files via unspecified vectors.",
"id": "GHSA-c2p9-cv2v-6744",
"modified": "2026-06-03T15:30:42Z",
"published": "2026-06-03T15:30:42Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-47273"
},
{
"type": "WEB",
"url": "https://www.synology.com/en-global/releaseNote/HyperBackup?model=DS224%2B\u0026os=DSM\u0026version=7_x_series"
}
],
"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"
}
]
}
GHSA-C2P9-H64P-QVV4
Vulnerability from github – Published: 2022-11-10 19:01 – Updated: 2022-11-16 19:00A Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') vulnerability in spacewalk/Uyuni of SUSE Linux Enterprise Module for SUSE Manager Server 4.2, SUSE Linux Enterprise Module for SUSE Manager Server 4.3, SUSE Manager Server 4.2 allows remote attackers to read files available to the user running the process, typically tomcat. This issue affects: SUSE Linux Enterprise Module for SUSE Manager Server 4.2 hub-xmlrpc-api-0.7-150300.3.9.2, inter-server-sync-0.2.4-150300.8.25.2, locale-formula-0.3-150300.3.3.2, py27-compat-salt-3000.3-150300.7.7.26.2, python-urlgrabber-3.10.2.1py2_3-150300.3.3.2, spacecmd-4.2.20-150300.4.30.2, spacewalk-backend-4.2.25-150300.4.32.4, spacewalk-client-tools-4.2.21-150300.4.27.3, spacewalk-java-4.2.43-150300.3.48.2, spacewalk-utils-4.2.18-150300.3.21.2, spacewalk-web-4.2.30-150300.3.30.3, susemanager-4.2.38-150300.3.44.3, susemanager-doc-indexes-4.2-150300.12.36.3, susemanager-docs_en-4.2-150300.12.36.2, susemanager-schema-4.2.25-150300.3.30.3, susemanager-sls versions prior to 4.2.28. SUSE Linux Enterprise Module for SUSE Manager Server 4.3 spacewalk-java versions prior to 4.3.39. SUSE Manager Server 4.2 release-notes-susemanager versions prior to 4.2.10.
{
"affected": [],
"aliases": [
"CVE-2022-43753"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-11-10T15:15:00Z",
"severity": "MODERATE"
},
"details": "A Improper Limitation of a Pathname to a Restricted Directory (\u0027Path Traversal\u0027) vulnerability in spacewalk/Uyuni of SUSE Linux Enterprise Module for SUSE Manager Server 4.2, SUSE Linux Enterprise Module for SUSE Manager Server 4.3, SUSE Manager Server 4.2 allows remote attackers to read files available to the user running the process, typically tomcat. This issue affects: SUSE Linux Enterprise Module for SUSE Manager Server 4.2 hub-xmlrpc-api-0.7-150300.3.9.2, inter-server-sync-0.2.4-150300.8.25.2, locale-formula-0.3-150300.3.3.2, py27-compat-salt-3000.3-150300.7.7.26.2, python-urlgrabber-3.10.2.1py2_3-150300.3.3.2, spacecmd-4.2.20-150300.4.30.2, spacewalk-backend-4.2.25-150300.4.32.4, spacewalk-client-tools-4.2.21-150300.4.27.3, spacewalk-java-4.2.43-150300.3.48.2, spacewalk-utils-4.2.18-150300.3.21.2, spacewalk-web-4.2.30-150300.3.30.3, susemanager-4.2.38-150300.3.44.3, susemanager-doc-indexes-4.2-150300.12.36.3, susemanager-docs_en-4.2-150300.12.36.2, susemanager-schema-4.2.25-150300.3.30.3, susemanager-sls versions prior to 4.2.28. SUSE Linux Enterprise Module for SUSE Manager Server 4.3 spacewalk-java versions prior to 4.3.39. SUSE Manager Server 4.2 release-notes-susemanager versions prior to 4.2.10.",
"id": "GHSA-c2p9-h64p-qvv4",
"modified": "2022-11-16T19:00:26Z",
"published": "2022-11-10T19:01:09Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-43753"
},
{
"type": "WEB",
"url": "https://bugzilla.suse.com/show_bug.cgi?id=1204716"
}
],
"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-C2PP-46RF-CQG2
Vulnerability from github – Published: 2022-05-02 06:12 – Updated: 2022-05-02 06:12Directory traversal vulnerability in the ccNewsletter (com_ccnewsletter) component 1.0.5 for Joomla! allows remote attackers to read arbitrary files via a .. (dot dot) in the controller parameter in a ccnewsletter action to index.php.
{
"affected": [],
"aliases": [
"CVE-2010-0467"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2010-02-02T17:30:00Z",
"severity": "MODERATE"
},
"details": "Directory traversal vulnerability in the ccNewsletter (com_ccnewsletter) component 1.0.5 for Joomla! allows remote attackers to read arbitrary files via a .. (dot dot) in the controller parameter in a ccnewsletter action to index.php.",
"id": "GHSA-c2pp-46rf-cqg2",
"modified": "2022-05-02T06:12:55Z",
"published": "2022-05-02T06:12:55Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2010-0467"
},
{
"type": "WEB",
"url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/55953"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/38378"
},
{
"type": "WEB",
"url": "http://www.chillcreations.com/en/blog/ccnewsletter-joomla-newsletter/ccnewsletter-106-security-release.html"
},
{
"type": "WEB",
"url": "http://www.exploit-db.com/exploits/11277"
},
{
"type": "WEB",
"url": "http://www.exploit-db.com/exploits/11282"
},
{
"type": "WEB",
"url": "http://www.securityfocus.com/bid/37987"
}
],
"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-C2QF-9GP9-PQG9
Vulnerability from github – Published: 2022-04-16 00:00 – Updated: 2022-05-17 00:01Multiple vulnerabilities in the Cisco IOx application hosting environment on multiple Cisco platforms could allow an attacker to inject arbitrary commands into the underlying host operating system, execute arbitrary code on the underlying host operating system, install applications without being authenticated, or conduct a cross-site scripting (XSS) attack against a user of the affected software. For more information about these vulnerabilities, see the Details section of this advisory.
{
"affected": [],
"aliases": [
"CVE-2022-20725"
],
"database_specific": {
"cwe_ids": [
"CWE-22",
"CWE-79"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-04-15T15:15:00Z",
"severity": "MODERATE"
},
"details": "Multiple vulnerabilities in the Cisco IOx application hosting environment on multiple Cisco platforms could allow an attacker to inject arbitrary commands into the underlying host operating system, execute arbitrary code on the underlying host operating system, install applications without being authenticated, or conduct a cross-site scripting (XSS) attack against a user of the affected software. For more information about these vulnerabilities, see the Details section of this advisory.",
"id": "GHSA-c2qf-9gp9-pqg9",
"modified": "2022-05-17T00:01:43Z",
"published": "2022-04-16T00:00:48Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/orangecertcc/security-research/security/advisories/GHSA-q2v9-qpmg-4qc4"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-20725"
},
{
"type": "WEB",
"url": "https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iox-yuXQ6hFj"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-C2QQ-2J48-5PR5
Vulnerability from github – Published: 2024-02-20 15:31 – Updated: 2024-02-20 15:31A relative path traversal in Fortinet FortiManager version 7.4.0 and 7.2.0 through 7.2.3 and 7.0.0 through 7.0.8 and 6.4.0 through 6.4.12 and 6.2.0 through 6.2.11 allows attacker to execute unauthorized code or commands via crafted HTTP requests.
{
"affected": [],
"aliases": [
"CVE-2023-42791"
],
"database_specific": {
"cwe_ids": [
"CWE-22",
"CWE-23"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-02-20T14:15:08Z",
"severity": "HIGH"
},
"details": "A relative path traversal in Fortinet FortiManager version 7.4.0 and 7.2.0 through 7.2.3 and 7.0.0 through 7.0.8 and 6.4.0 through 6.4.12 and 6.2.0 through 6.2.11 allows attacker to execute unauthorized code or commands via crafted HTTP requests.",
"id": "GHSA-c2qq-2j48-5pr5",
"modified": "2024-02-20T15:31:04Z",
"published": "2024-02-20T15:31:04Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-42791"
},
{
"type": "WEB",
"url": "https://fortiguard.com/psirt/FG-IR-23-189"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-C2QR-H2Q8-3PFQ
Vulnerability from github – Published: 2024-10-08 18:33 – Updated: 2024-10-08 18:33Path Traversal in Ivanti Avalanche before version 6.4.5 allows a remote unauthenticated attacker to leak sensitive information
{
"affected": [],
"aliases": [
"CVE-2024-47011"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-10-08T17:15:55Z",
"severity": "HIGH"
},
"details": "Path Traversal in Ivanti Avalanche before version 6.4.5 allows a remote unauthenticated attacker to leak sensitive information",
"id": "GHSA-c2qr-h2q8-3pfq",
"modified": "2024-10-08T18:33:13Z",
"published": "2024-10-08T18:33:13Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-47011"
},
{
"type": "WEB",
"url": "https://forums.ivanti.com/s/article/Ivanti-Avalanche-6-4-5-Security-Advisory"
}
],
"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-C2RH-3265-VP8C
Vulnerability from github – Published: 2022-05-02 03:42 – Updated: 2022-05-02 03:42Directory traversal vulnerability in Anantasoft Gazelle CMS 1.0 allows remote attackers to overwrite arbitrary files via a .. (dot dot) in the customizetemplate parameter in a direct request to admin/settemplate.php.
{
"affected": [],
"aliases": [
"CVE-2009-3181"
],
"database_specific": {
"cwe_ids": [
"CWE-22"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2009-09-11T20:30:00Z",
"severity": "MODERATE"
},
"details": "Directory traversal vulnerability in Anantasoft Gazelle CMS 1.0 allows remote attackers to overwrite arbitrary files via a .. (dot dot) in the customizetemplate parameter in a direct request to admin/settemplate.php.",
"id": "GHSA-c2rh-3265-vp8c",
"modified": "2022-05-02T03:42:32Z",
"published": "2022-05-02T03:42:32Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2009-3181"
},
{
"type": "WEB",
"url": "http://secunia.com/advisories/33686"
},
{
"type": "WEB",
"url": "http://www.exploit-db.com/exploits/9425"
}
],
"schema_version": "1.4.0",
"severity": []
}
Mitigation MIT-5.1
Strategy: Input Validation
- Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
- When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue."
- Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
- When validating filenames, use stringent allowlists that limit the character set to be used. If feasible, only allow a single "." character in the filename to avoid weaknesses such as CWE-23, and exclude directory separators such as "/" to avoid CWE-36. Use a list of allowable file extensions, which will help to avoid CWE-434.
- Do not rely exclusively on a filtering mechanism that removes potentially dangerous characters. This is equivalent to a denylist, which may be incomplete (CWE-184). For example, filtering "/" is insufficient protection if the filesystem also supports the use of "\" as a directory separator. Another possible error could occur when the filtering is applied in a way that still produces dangerous data (CWE-182). For example, if "../" sequences are removed from the ".../...//" string in a sequential fashion, two instances of "../" would be removed from the original string, but the remaining characters would still form the "../" string.
Mitigation MIT-15
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
Mitigation MIT-20.1
Strategy: Input Validation
- Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass allowlist validation schemes by introducing dangerous inputs after they have been checked.
- Use a built-in path canonicalization function (such as realpath() in C) that produces the canonical version of the pathname, which effectively removes ".." sequences and symbolic links (CWE-23, CWE-59). This includes:
- realpath() in C
- getCanonicalPath() in Java
- GetFullPath() in ASP.NET
- realpath() or abs_path() in Perl
- realpath() in PHP
Mitigation MIT-4
Strategy: Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482].
Mitigation MIT-29
Strategy: Firewall
Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth [REF-1481].
Mitigation MIT-17
Strategy: Environment Hardening
Run your code using the lowest privileges that are required to accomplish the necessary tasks [REF-76]. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment. For example, database applications rarely need to run as the database administrator, especially in day-to-day operations.
Mitigation MIT-21.1
Strategy: Enforcement by Conversion
- When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.
- For example, ID 1 could map to "inbox.txt" and ID 2 could map to "profile.txt". Features such as the ESAPI AccessReferenceMap [REF-185] provide this capability.
Mitigation MIT-22
Strategy: Sandbox or Jail
- Run the code in a "jail" or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.
- OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations.
- This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise.
- Be careful to avoid CWE-243 and other weaknesses related to jails.
Mitigation MIT-34
Strategy: Attack Surface Reduction
- Store library, include, and utility files outside of the web document root, if possible. Otherwise, store them in a separate directory and use the web server's access control capabilities to prevent attackers from directly requesting them. One common practice is to define a fixed constant in each calling program, then check for the existence of the constant in the library/include file; if the constant does not exist, then the file was directly requested, and it can exit immediately.
- This significantly reduces the chance of an attacker being able to bypass any protection mechanisms that are in the base program but not in the include files. It will also reduce the attack surface.
Mitigation MIT-39
- Ensure that error messages only contain minimal details that are useful to the intended audience and no one else. The messages need to strike the balance between being too cryptic (which can confuse users) or being too detailed (which may reveal more than intended). The messages should not reveal the methods that were used to determine the error. Attackers can use detailed information to refine or optimize their original attack, thereby increasing their chances of success.
- If errors must be captured in some detail, record them in log messages, but consider what could occur if the log messages can be viewed by attackers. Highly sensitive information such as passwords should never be saved to log files.
- Avoid inconsistent messaging that might accidentally tip off an attacker about internal state, such as whether a user account exists or not.
- In the context of path traversal, error messages which disclose path information can help attackers craft the appropriate attack strings to move through the file system hierarchy.
Mitigation MIT-16
Strategy: Environment Hardening
When using PHP, configure the application so that it does not use register_globals. During implementation, develop the application so that it does not rely on this feature, but be wary of implementing a register_globals emulation that is subject to weaknesses such as CWE-95, CWE-621, and similar issues.
CAPEC-126: Path Traversal
An adversary uses path manipulation methods to exploit insufficient input validation of a target to obtain access to data that should be not be retrievable by ordinary well-formed requests. A typical variety of this attack involves specifying a path to a desired file together with dot-dot-slash characters, resulting in the file access API or function traversing out of the intended directory structure and into the root file system. By replacing or modifying the expected path information the access function or API retrieves the file desired by the attacker. These attacks either involve the attacker providing a complete path to a targeted file or using control characters (e.g. path separators (/ or \) and/or dots (.)) to reach desired directories or files.
CAPEC-64: Using Slashes and URL Encoding Combined to Bypass Validation Logic
This attack targets the encoding of the URL combined with the encoding of the slash characters. An attacker can take advantage of the multiple ways of encoding a URL and abuse the interpretation of the URL. A URL may contain special character that need special syntax handling in order to be interpreted. Special characters are represented using a percentage character followed by two digits representing the octet code of the original character (%HEX-CODE). For instance US-ASCII space character would be represented with %20. This is often referred as escaped ending or percent-encoding. Since the server decodes the URL from the requests, it may restrict the access to some URL paths by validating and filtering out the URL requests it received. An attacker will try to craft an URL with a sequence of special characters which once interpreted by the server will be equivalent to a forbidden URL. It can be difficult to protect against this attack since the URL can contain other format of encoding such as UTF-8 encoding, Unicode-encoding, etc.
CAPEC-76: Manipulating Web Input to File System Calls
An attacker manipulates inputs to the target software which the target software passes to file system calls in the OS. The goal is to gain access to, and perhaps modify, areas of the file system that the target software did not intend to be accessible.
CAPEC-78: Using Escaped Slashes in Alternate Encoding
This attack targets the use of the backslash in alternate encoding. An adversary can provide a backslash as a leading character and causes a parser to believe that the next character is special. This is called an escape. By using that trick, the adversary tries to exploit alternate ways to encode the same character which leads to filter problems and opens avenues to attack.
CAPEC-79: Using Slashes in Alternate Encoding
This attack targets the encoding of the Slash characters. An adversary would try to exploit common filtering problems related to the use of the slashes characters to gain access to resources on the target host. Directory-driven systems, such as file systems and databases, typically use the slash character to indicate traversal between directories or other container components. For murky historical reasons, PCs (and, as a result, Microsoft OSs) choose to use a backslash, whereas the UNIX world typically makes use of the forward slash. The schizophrenic result is that many MS-based systems are required to understand both forms of the slash. This gives the adversary many opportunities to discover and abuse a number of common filtering problems. The goal of this pattern is to discover server software that only applies filters to one version, but not the other.