CWE-434
AllowedUnrestricted Upload of File with Dangerous Type
Abstraction: Base · Status: Draft
The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.
6008 vulnerabilities reference this CWE, most recent first.
GHSA-CW6Q-XW7J-7MH5
Vulnerability from github – Published: 2023-07-21 03:30 – Updated: 2023-07-21 03:30A vulnerability, which was classified as critical, was found in SourceCodester House Rental and Property Listing System 1.0. Affected is an unknown function of the file btn_functions.php. The manipulation leads to unrestricted upload. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used. VDB-235074 is the identifier assigned to this vulnerability.
{
"affected": [],
"aliases": [
"CVE-2023-3806"
],
"database_specific": {
"cwe_ids": [
"CWE-434"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-07-21T02:15:10Z",
"severity": "MODERATE"
},
"details": "A vulnerability, which was classified as critical, was found in SourceCodester House Rental and Property Listing System 1.0. Affected is an unknown function of the file btn_functions.php. The manipulation leads to unrestricted upload. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used. VDB-235074 is the identifier assigned to this vulnerability.",
"id": "GHSA-cw6q-xw7j-7mh5",
"modified": "2023-07-21T03:30:26Z",
"published": "2023-07-21T03:30:26Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-3806"
},
{
"type": "WEB",
"url": "https://github.com/GZRsecurity/Cve-System/blob/main/House%20Rental%20and%20Property%20Listing%20System%20register.php%20has%20%20File%20Upload(RCE)%20Vulnerability.pdf"
},
{
"type": "WEB",
"url": "https://vuldb.com/?ctiid.235074"
},
{
"type": "WEB",
"url": "https://vuldb.com/?id.235074"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L",
"type": "CVSS_V3"
}
]
}
GHSA-CW8F-MXFW-5MRX
Vulnerability from github – Published: 2024-04-18 12:30 – Updated: 2024-04-18 12:30A vulnerability was found in SourceCodester Home Clean Service System 1.0. It has been rated as critical. Affected by this issue is some unknown functionality of the file \admin\student.add.php of the component Photo Handler. The manipulation leads to unrestricted upload. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-261440.
{
"affected": [],
"aliases": [
"CVE-2024-3948"
],
"database_specific": {
"cwe_ids": [
"CWE-434"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-04-18T11:15:39Z",
"severity": "MODERATE"
},
"details": "A vulnerability was found in SourceCodester Home Clean Service System 1.0. It has been rated as critical. Affected by this issue is some unknown functionality of the file \\admin\\student.add.php of the component Photo Handler. The manipulation leads to unrestricted upload. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-261440.",
"id": "GHSA-cw8f-mxfw-5mrx",
"modified": "2024-04-18T12:30:31Z",
"published": "2024-04-18T12:30:31Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-3948"
},
{
"type": "WEB",
"url": "https://github.com/xuanluansec/vul/issues/5"
},
{
"type": "WEB",
"url": "https://vuldb.com/?ctiid.261440"
},
{
"type": "WEB",
"url": "https://vuldb.com/?id.261440"
},
{
"type": "WEB",
"url": "https://vuldb.com/?submit.318722"
}
],
"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"
}
]
}
GHSA-CWCG-79P4-F24H
Vulnerability from github – Published: 2026-06-10 09:31 – Updated: 2026-06-10 12:33The Schema & Structured Data for WP & AMP WordPress plugin before 1.60 does not check user capabilities on its frontend AJAX file-upload handlers and does not validate the actual content of uploaded files against the endpoint's intended media type, allowing unauthenticated users to upload any file type accepted by WordPress's media library through endpoints that should only accept images or videos.
{
"affected": [],
"aliases": [
"CVE-2026-9067"
],
"database_specific": {
"cwe_ids": [
"CWE-434"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-06-10T07:16:25Z",
"severity": "CRITICAL"
},
"details": "The Schema \u0026 Structured Data for WP \u0026 AMP WordPress plugin before 1.60 does not check user capabilities on its frontend AJAX file-upload handlers and does not validate the actual content of uploaded files against the endpoint\u0027s intended media type, allowing unauthenticated users to upload any file type accepted by WordPress\u0027s media library through endpoints that should only accept images or videos.",
"id": "GHSA-cwcg-79p4-f24h",
"modified": "2026-06-10T12:33:22Z",
"published": "2026-06-10T09:31:57Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-9067"
},
{
"type": "WEB",
"url": "https://wpscan.com/vulnerability/7fac98eb-f82c-4705-a956-aba650945826"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-CWF8-44X6-32C2
Vulnerability from github – Published: 2026-04-03 02:49 – Updated: 2026-05-06 21:22Summary
OpenShell Mirror Sync: Sandbox Escape via Unrestricted File Sync + Symlink Traversal
Current Maintainer Triage
- Status: narrow
- Normalized severity: high
- Assessment: v2026.3.28 still has the mirror-boundary bug because shipped c02ee8 only excluded hooks while unreleased 3b9dab is the first full symlink-free upload and download hardening.
Affected Packages / Versions
- Package:
openclaw(npm) - Latest published npm version:
2026.3.31 - Vulnerable version range:
<=2026.3.28 - Patched versions:
>= 2026.3.31 - First stable tag containing the fix:
v2026.3.31
Fix Commit(s)
c02ee8a3a4cb390b23afdf21317aa8b2096854d1— 2026-03-25T19:59:07Z3b9dab0ece4643a9643e6a45459f5c709d3ce320— 2026-03-30T14:51:44+01:00
OpenClaw thanks @AntAISecurityLab for reporting.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 2026.3.28"
},
"package": {
"ecosystem": "npm",
"name": "openclaw"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2026.3.31"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-41397"
],
"database_specific": {
"cwe_ids": [
"CWE-434",
"CWE-59"
],
"github_reviewed": true,
"github_reviewed_at": "2026-04-03T02:49:14Z",
"nvd_published_at": "2026-04-28T19:37:43Z",
"severity": "HIGH"
},
"details": "## Summary\nOpenShell Mirror Sync: Sandbox Escape via Unrestricted File Sync + Symlink Traversal\n\n## Current Maintainer Triage\n- Status: narrow\n- Normalized severity: high\n- Assessment: v2026.3.28 still has the mirror-boundary bug because shipped c02ee8 only excluded hooks while unreleased 3b9dab is the first full symlink-free upload and download hardening.\n\n## Affected Packages / Versions\n- Package: `openclaw` (npm)\n- Latest published npm version: `2026.3.31`\n- Vulnerable version range: `\u003c=2026.3.28`\n- Patched versions: `\u003e= 2026.3.31`\n- First stable tag containing the fix: `v2026.3.31`\n\n## Fix Commit(s)\n- `c02ee8a3a4cb390b23afdf21317aa8b2096854d1` \u2014 2026-03-25T19:59:07Z\n- `3b9dab0ece4643a9643e6a45459f5c709d3ce320` \u2014 2026-03-30T14:51:44+01:00\n\nOpenClaw thanks @AntAISecurityLab for reporting.",
"id": "GHSA-cwf8-44x6-32c2",
"modified": "2026-05-06T21:22:37Z",
"published": "2026-04-03T02:49:14Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/openclaw/openclaw/security/advisories/GHSA-cwf8-44x6-32c2"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-41397"
},
{
"type": "WEB",
"url": "https://github.com/openclaw/openclaw/commit/3b9dab0ece4643a9643e6a45459f5c709d3ce320"
},
{
"type": "WEB",
"url": "https://github.com/openclaw/openclaw/commit/c02ee8a3a4cb390b23afdf21317aa8b2096854d1"
},
{
"type": "PACKAGE",
"url": "https://github.com/openclaw/openclaw"
},
{
"type": "WEB",
"url": "https://github.com/openclaw/openclaw/releases/tag/v2026.3.31"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/openclaw-sandbox-escape-via-unrestricted-file-sync-and-symlink-traversal"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "OpenClaw: OpenShell Mirror Sync \u2014 Sandbox Escape via Unrestricted File Sync + Symlink Traversal"
}
GHSA-CWGM-QW8V-HRRG
Vulnerability from github – Published: 2022-05-17 02:39 – Updated: 2023-07-27 21:06Dolibarr ERP/CRM 5.0.3 and prior allows low-privilege users to upload files of dangerous types, which can result in arbitrary code execution within the context of the vulnerable application.
{
"affected": [
{
"package": {
"ecosystem": "Packagist",
"name": "dolibarr/dolibarr"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"last_affected": "5.0.3"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2017-9840"
],
"database_specific": {
"cwe_ids": [
"CWE-434"
],
"github_reviewed": true,
"github_reviewed_at": "2023-07-27T21:06:34Z",
"nvd_published_at": "2017-06-25T12:29:00Z",
"severity": "HIGH"
},
"details": "Dolibarr ERP/CRM 5.0.3 and prior allows low-privilege users to upload files of dangerous types, which can result in arbitrary code execution within the context of the vulnerable application.",
"id": "GHSA-cwgm-qw8v-hrrg",
"modified": "2023-07-27T21:06:34Z",
"published": "2022-05-17T02:39:25Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2017-9840"
},
{
"type": "WEB",
"url": "https://www.wizlynxgroup.com/security-research-advisories/vuln/WLX-2017-009"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
],
"summary": "Dolibarr ERP and CRM Unsafe File Upload Vulnerability"
}
GHSA-CWH7-P5VC-3C9X
Vulnerability from github – Published: 2025-11-11 18:30 – Updated: 2025-11-11 18:30Unrestricted upload of file with dangerous type for some Intel(R) CIP software before version WIN_DCA_2.4.0.11001 within Ring 3: User Applications may allow an escalation of privilege. Unprivileged software adversary with a privileged user combined with a high complexity attack may enable data manipulation. This result may potentially occur via network access when attack requirements are present with special internal knowledge and requires passive user interaction. The potential vulnerability may impact the confidentiality (none), integrity (low) and availability (none) of the vulnerable system, resulting in subsequent system confidentiality (none), integrity (none) and availability (none) impacts.
{
"affected": [],
"aliases": [
"CVE-2025-24862"
],
"database_specific": {
"cwe_ids": [
"CWE-434"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-11-11T17:15:43Z",
"severity": "LOW"
},
"details": "Unrestricted upload of file with dangerous type for some Intel(R) CIP software before version WIN_DCA_2.4.0.11001 within Ring 3: User Applications may allow an escalation of privilege. Unprivileged software adversary with a privileged user combined with a high complexity attack may enable data manipulation. This result may potentially occur via network access when attack requirements are present with special internal knowledge and requires passive user interaction. The potential vulnerability may impact the confidentiality (none), integrity (low) and availability (none) of the vulnerable system, resulting in subsequent system confidentiality (none), integrity (none) and availability (none) impacts.",
"id": "GHSA-cwh7-p5vc-3c9x",
"modified": "2025-11-11T18:30:18Z",
"published": "2025-11-11T18:30:18Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-24862"
},
{
"type": "WEB",
"url": "https://intel.com/content/www/us/en/security-center/advisory/intel-sa-01328.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:H/UI:R/S:U/C:N/I:L/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:H/UI:P/VC:N/VI:L/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-CWPG-W65C-X3H2
Vulnerability from github – Published: 2023-01-19 21:30 – Updated: 2023-01-25 21:30PopojiCMS v2.0.1 backend plugin function has a file upload vulnerability.
{
"affected": [],
"aliases": [
"CVE-2022-47766"
],
"database_specific": {
"cwe_ids": [
"CWE-434"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2023-01-19T19:15:00Z",
"severity": "HIGH"
},
"details": "PopojiCMS v2.0.1 backend plugin function has a file upload vulnerability.",
"id": "GHSA-cwpg-w65c-x3h2",
"modified": "2023-01-25T21:30:19Z",
"published": "2023-01-19T21:30:27Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-47766"
},
{
"type": "WEB",
"url": "https://github.com/PopojiCMS/PopojiCMS/issues/35"
}
],
"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-CWPX-HFWR-748Q
Vulnerability from github – Published: 2024-04-24 09:30 – Updated: 2026-04-01 18:31Unrestricted Upload of File with Dangerous Type vulnerability in WP Lab WP-Lister Lite for eBay.This issue affects WP-Lister Lite for eBay: from n/a through 3.5.11.
{
"affected": [],
"aliases": [
"CVE-2024-32836"
],
"database_specific": {
"cwe_ids": [
"CWE-434"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-04-24T08:15:41Z",
"severity": "CRITICAL"
},
"details": "Unrestricted Upload of File with Dangerous Type vulnerability in WP Lab WP-Lister Lite for eBay.This issue affects WP-Lister Lite for eBay: from n/a through 3.5.11.",
"id": "GHSA-cwpx-hfwr-748q",
"modified": "2026-04-01T18:31:46Z",
"published": "2024-04-24T09:30:32Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-32836"
},
{
"type": "WEB",
"url": "https://patchstack.com/database/Wordpress/Plugin/wp-lister-for-ebay/vulnerability/wordpress-wp-lister-lite-for-ebay-plugin-3-5-11-arbitrary-file-upload-vulnerability?_s_id=cve"
},
{
"type": "WEB",
"url": "https://patchstack.com/database/vulnerability/wp-lister-for-ebay/wordpress-wp-lister-lite-for-ebay-plugin-3-5-11-arbitrary-file-upload-vulnerability?_s_id=cve"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-CWQ2-35X4-44PQ
Vulnerability from github – Published: 2026-04-18 06:30 – Updated: 2026-04-18 06:30The CMP – Coming Soon & Maintenance Plugin by NiteoThemes plugin for WordPress is vulnerable to arbitrary file upload and remote code execution in all versions up to, and including, 4.1.16 via the cmp_theme_update_install AJAX action. This is due to the function only checking for the publish_pages capability (available to Editors and above) instead of manage_options (Administrators only), combined with a lack of proper validation on the user-supplied file URL and no verification of the downloaded file's content before extraction. This makes it possible for authenticated attackers, with Administrator-level access and above, to force the server to download and extract a malicious ZIP file from a remote attacker-controlled URL into a web-accessible directory (wp-content/plugins/cmp-premium-themes/), resulting in remote code execution. Due to the lack of a nonce for Editors, they are unable to exploit this vulnerability.
{
"affected": [],
"aliases": [
"CVE-2026-6518"
],
"database_specific": {
"cwe_ids": [
"CWE-434"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-04-18T05:16:24Z",
"severity": "HIGH"
},
"details": "The CMP \u2013 Coming Soon \u0026 Maintenance Plugin by NiteoThemes plugin for WordPress is vulnerable to arbitrary file upload and remote code execution in all versions up to, and including, 4.1.16 via the `cmp_theme_update_install` AJAX action. This is due to the function only checking for the `publish_pages` capability (available to Editors and above) instead of `manage_options` (Administrators only), combined with a lack of proper validation on the user-supplied file URL and no verification of the downloaded file\u0027s content before extraction. This makes it possible for authenticated attackers, with Administrator-level access and above, to force the server to download and extract a malicious ZIP file from a remote attacker-controlled URL into a web-accessible directory (`wp-content/plugins/cmp-premium-themes/`), resulting in remote code execution. Due to the lack of a nonce for Editors, they are unable to exploit this vulnerability.",
"id": "GHSA-cwq2-35x4-44pq",
"modified": "2026-04-18T06:30:14Z",
"published": "2026-04-18T06:30:14Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-6518"
},
{
"type": "WEB",
"url": "https://plugins.trac.wordpress.org/browser/cmp-coming-soon-maintenance/tags/4.1.16/niteo-cmp.php#L1421"
},
{
"type": "WEB",
"url": "https://plugins.trac.wordpress.org/browser/cmp-coming-soon-maintenance/tags/4.1.16/niteo-cmp.php#L1437"
},
{
"type": "WEB",
"url": "https://plugins.trac.wordpress.org/browser/cmp-coming-soon-maintenance/tags/4.1.16/niteo-cmp.php#L1447"
},
{
"type": "WEB",
"url": "https://plugins.trac.wordpress.org/changeset?old_path=%2Fcmp-coming-soon-maintenance/tags/4.1.16\u0026new_path=%2Fcmp-coming-soon-maintenance/tags/4.1.17"
},
{
"type": "WEB",
"url": "https://www.wordfence.com/threat-intel/vulnerabilities/id/d6fb275b-dbba-46df-b170-977ef4a84c4c?source=cve"
}
],
"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-CWV5-FQMQ-FWM6
Vulnerability from github – Published: 2024-07-25 21:31 – Updated: 2024-08-01 15:32An arbitrary file upload vulnerability in Webkul Qloapps v1.6.0.0 allows attackers to execute arbitrary code via uploading a crafted file.
{
"affected": [],
"aliases": [
"CVE-2024-40318"
],
"database_specific": {
"cwe_ids": [
"CWE-434"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2024-07-25T19:15:10Z",
"severity": "HIGH"
},
"details": "An arbitrary file upload vulnerability in Webkul Qloapps v1.6.0.0 allows attackers to execute arbitrary code via uploading a crafted file.",
"id": "GHSA-cwv5-fqmq-fwm6",
"modified": "2024-08-01T15:32:10Z",
"published": "2024-07-25T21:31:20Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-40318"
},
{
"type": "WEB",
"url": "https://github.com/3v1lC0d3/RCE-QloApps/blob/main/qloapps--RCE.pdf"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
Mitigation
Generate a new, unique filename for an uploaded file instead of using the user-supplied filename, so that no external input is used at all.[REF-422] [REF-423]
Mitigation MIT-21
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.
Mitigation
Consider storing the uploaded files outside of the web document root entirely. Then, use other mechanisms to deliver the files dynamically. [REF-423]
Mitigation MIT-5
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.
- For example, limiting filenames to alphanumeric characters can help to restrict the introduction of unintended file extensions.
Mitigation
Define a very limited set of allowable extensions and only generate filenames that end in these extensions. Consider the possibility of XSS (CWE-79) before allowing .html or .htm file types.
Mitigation
Strategy: Input Validation
Ensure that only one extension is used in the filename. Some web servers, including some versions of Apache, may process files based on inner extensions so that "filename.php.gif" is fed to the PHP interpreter.[REF-422] [REF-423]
Mitigation
When running on a web server that supports case-insensitive filenames, perform case-insensitive evaluations of the extensions that are provided.
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
Do not rely exclusively on sanity checks of file contents to ensure that the file is of the expected type and size. It may be possible for an attacker to hide code in some file segments that will still be executed by the server. For example, GIF images may contain a free-form comments field.
Mitigation
Do not rely exclusively on the MIME content type or filename attribute when determining how to render a file. Validating the MIME content type and ensuring that it matches the extension is only a partial solution.
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-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.
CAPEC-1: Accessing Functionality Not Properly Constrained by ACLs
In applications, particularly web applications, access to functionality is mitigated by an authorization framework. This framework maps Access Control Lists (ACLs) to elements of the application's functionality; particularly URL's for web apps. In the case that the administrator failed to specify an ACL for a particular element, an attacker may be able to access it with impunity. An attacker with the ability to access functionality not properly constrained by ACLs can obtain sensitive information and possibly compromise the entire application. Such an attacker can access resources that must be available only to users at a higher privilege level, can access management sections of the application, or can run queries for data that they otherwise not supposed to.