CVE-2026-100370
The weakness is that "javascript:" is rejected as a scheme, while "data:" is rejected only when the literal substring onload appears in the URL value (/^data:.*onload/i).
Does this matter?
Lower severity and a low EPSS score (0.27%). Track it; it rarely justifies an emergency change on its own.
Description
DOMSanitizer is a DOM/SVG/MathML Sanitizer for PHP 7.3+. Prior to version 1.0.15, the isDangerousUrl() method is responsible for rejecting dangerous URL values in the href and xlink:href attributes. The weakness is that "javascript:" is rejected as a scheme, while "data:" is rejected only when the literal substring onload appears in the URL value (/^data:.*onload/i). Because data: payloads are routinely Base64-encoded, the dangerous content (<script>, event handlers, etc.) is invisible to that substring test. A URL such as data:text/html;base64,… therefore survives in href / xlink:href, even though the decoded payload is active markup. This is an incomplete input-validation / sanitization defect in the sanitizer itself. This issue has been patched in version 1.0.15.
- CVSS 3.1
- 4.7 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N
- EPSS
- 0.27% probability · 20th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-20
- Source
- security-advisories@github.com
EPSS moved from 0.3% on 29 September 2026 to 0.3% on 26 October 2026.
References
- https://github.com/rhukster/dom-sanitizer/commit/10f97807e4501d60f63987f2e76a38cdbf312dcb
- https://github.com/rhukster/dom-sanitizer/commit/fb8f758b41134fc5fb2f563666f2330c69e31f94
- https://github.com/rhukster/dom-sanitizer/releases/tag/1.0.15
- https://github.com/rhukster/dom-sanitizer/security/advisories/GHSA-wcj2-r6vg-rm97
- https://github.com/rhukster/dom-sanitizer/security/advisories/GHSA-wcj2-r6vg-rm97
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.