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Medium

Contao: Path traversal in the images controller

  • Disclosed: 09.10.2026
  • Updated: 11.10.2026 10:31

ImagesController joins the user-controlled {path} onto the configured image target directory with Path::join(), which canonicalises .. segments, and never calls Path::isBasePath() to confirm the result stayed inside that directory. An unauthenticated GET request with percent-encoded dot segments therefore escapes the directory, and the file is returned by BinaryFileResponse.

Reads are bounded to the extensions in contao.image.valid_extensions, and paths below the upload directory fail for an unrelated reason, so this is reported as a missing boundary check rather than as a general arbitrary file read. Both Apache with the shipped public/.htaccess and nginx with the documented configuration are affected.

Impact

Any unauthenticated visitor can read files that are deliberately kept outside the document root, anywhere under the project directory, as long as the name ends in one of contao.image.valid_extensions (jpg, jpeg, gif, png, tif, tiff, bmp, svg, svgz, webp).

The route also acts as an existence oracle for arbitrary paths, and on a debug-enabled instance the 404 message discloses the absolute filesystem path.

Honesty caveat, stated because it lowers the severity: Protected member folders could not be read using this issue: every path below the upload directory returns 500 for the reason given under Details, so the practically reachable set is image-typed files outside files/.

What to do

Update contao/core-bundle to version 5.3.50, 5.7.12, or later.

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Composer package contao/core-bundle >= 4.1.0, < 5.3.50, >= 5.4.0-RC1, < 5.7.12 5.3.50, 5.7.12

References

CVSS score 5.3/10
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Weakness (CWE)
CWE-22
Platform
Composer
Package
contao/core-bundle
Disclosed
09.10.2026
Updated
11.10.2026 10:31

Sources and licenses · Edited or translated by DockRay; source rights and applicable licenses are retained.

OSV / GitHub Advisory Database - GHSA-mrvp-7wmx-5m4h - CC BY 4.0

Vulnerability history: contao/core-bundle

All published vulnerabilities of this package (Composer package), newest first. Shows whether this is a one-off slip or a package that needs watching.

All (40) in the archive
Total entries
40
First → latest
12.2019 10.2026
Without a fix
0
Exploited in attacks
0

Severity breakdown

  • Critical 4
  • High 7
  • Medium 23
  • Low 6

Disclosures per year

Severity:
  1. Contao: Path traversal in the images controller this entry
    Medium · 5.3 CVE-2026-107844 >= 4.1.0, < 5.3.50, >= 5.4.0-RC1, < 5.7.12 5.3.50, 5.7.12
  2. Contao affected by remote command execution through file upload
    High · 8.3 CVE-2024-45398 >= 4.0.0, < 4.13.49, >= 5.0.0, < 5.3.15, >= 5.4.0, < 5.4.3 4.13.49, 5.3.15, 5.4.3
  3. Contao: Possible cookie sharing with external domains while checking protected pages for broken links
    High · 8.3 CVE-2024-28235 >= 4.9.0, < 4.13.40, >= 5.0.0-RC1, < 5.3.4 4.13.40, 5.3.4
  4. Contao SQL injection in the file manager
    Critical · 9.8 CVE-2019-11512 >= 4.1.0, < 4.4.39, >= 4.5.0, < 4.7.5 4.4.39, 4.7.5
  5. Contao SQL injection in the backend and listing module
    Critical · 9.8 CVE-2017-16558 >= 4.0.0, < 4.4.8, >= 3.0.0, <= 3.5.30 4.4.8
  6. Cross site scripting via canonical tag in Contao
    High · 7.2 CVE-2022-24899 >= 4.13.0, < 4.13.3 4.13.3
  7. Contao CSRF Token Bypass
    High · 8.8 CVE-2019-10642 >= 4.7.0, < 4.7.3 4.7.3
  8. Contao Does Not Invalidate Existing Sessions When Password Changes
    Critical · 9.8 CVE-2019-10641 >= 4.0.0, < 4.4.37, >= 4.5.0, < 4.7.3 4.4.37, 4.7.3
  9. Contao Core directory traversal vulnerability
    High · 8.8 CVE-2017-10993 >= 4.0.0, < 4.4.1 4.4.1
  10. Contao Does Not Expire Tokens Correctly
    Critical · 9.8 CVE-2019-10643 >= 4.7.0, < 4.7.3 4.7.3
  11. Privilege escalation via form generator
    High · 8.0 CVE-2021-37627 >= 4.0.0, < 4.4.56, >= 4.5.0, < 4.9.18, >= 4.10.0, < 4.11.7 4.4.56, 4.9.18, 4.11.7
  12. Unrestricted file uploads in Contao
    High · 8.8 CVE-2019-19745 >= 4.0.0, < 4.4.46, >= 4.5.0, < 4.8.6 4.4.46, 4.8.6

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