Craft CMS has authenticated path traversal in assets/icon, allowing local .svg file read

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

2.0 · CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N · score source

EPSS

• CVE-2026-56394: 0.49% estimated exploitation activity in the next 30 days; percentile 42.43 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary An authenticated path traversal in assets/icon allows local SVG file read by passing traversal sequences in the extension parameter. The issue is caused by file existence checks happening before extension validation. Details The endpoint: - src/controllers/AssetsController.php:1115-1123 - actionIcon(string $extension) calls Assets::iconPath($extension) and returns sendFile($path, ...). In Assets::iconPath(): - Path is built from user-controlled extension: - src/helpers/Assets.php:906-909 - If fileexists($path) is true, path is returned immediately: - src/helpers/Assets.php:910-912 Validation exists in Assets::iconSvg(): - pregmatch('/^\w+$/', $extension) - src/helpers/Assets.php:927-931 However, that validation is only reached if iconPath() does not find a file. So traversal payloads that resolve to existing .svg files bypass validation and are served by sendFile(). Impact - Authenticated users can read local .svg files accessible to the application process. References -…

Published by the source

9 Jul 2026, 13:44 UTC

Last modified by the source

6 Aug 2026, 21:58 UTC

Source last checked

26 Oct 2026, 14:50 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-c43v-4cr8-6mvp

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# Patch Next advisory brief: CVE-2026-56394

Advisory: Craft CMS has authenticated path traversal in `assets/icon`, allowing local `.svg` file read
IDs: CVE-2026-56394, GHSA-c43v-4cr8-6mvp
Record: https://patchnext.com/advisories/cve-2026-56394 (revision 1, source checked 26 Oct 2026, 14:50 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Low (CVSS 2.0)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: craftcms/cms 5.9.13, 4.17.7. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist craftcms/cms: affected >= 4.0.0-RC1, <= 4.17.6; >= 5.0.0-RC1, <= 5.9.12; fixed in 5.9.13, 4.17.7

## Suggested inspection (read-only)
- Packagist craftcms/cms: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on craftcms/cms.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-c43v-4cr8-6mvp (GitHub-reviewed advisory GHSA-c43v-4cr8-6mvp lists affected ranges: Packagist craftcms/cms >=4.0.0-RC1 =5.0.0-RC1 <=5.9.12)

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