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Medium

Cross site scripting via input unit widget

  • Disclosed: 25.07.2023
  • Updated: 11.10.2026 10:22

Impact

Authenticated users can inject malicious code in widgets with units, which is then executed both in the element preview (back end) and on the website (front end).

Patches

Update to Contao 4.9.42, 4.13.28 or 5.1.10.

Workarounds

Disable login for all untrusted back end users.

References

https://contao.org/en/security-advisories/cross-site-scripting-in-widgets-with-units

For more information

If you have any questions or comments about this advisory, open an issue in contao/contao.

Credits

Thanks to Christian Pöschl and Fabian Brenner from usd AG for reporting this vulnerability.

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Composer package contao/core-bundle >= 4.0.0, < 4.9.42, >= 4.10.0, < 4.13.28, >= 5.0.0, < 5.1.10 4.9.42, 4.13.28, 5.1.10

References

CVSS score 6.6/10
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:L/I:L/A:L
Weakness (CWE)
CWE-79
Platform
Composer
Package
contao/core-bundle
Disclosed
25.07.2023
Updated
11.10.2026 10:22

Sources and licenses

OSV / GitHub Advisory Database - GHSA-4gpr-p634-922x - 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 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
  2. 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
  3. Cross site scripting via input unit widget this entry
    Medium · 6.6 CVE-2023-36806 >= 4.0.0, < 4.9.42, >= 4.10.0, < 4.13.28, >= 5.0.0, < 5.1.10 4.9.42, 4.13.28, 5.1.10
  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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