CVE-2026-47345
TYPO3 HTML Sanitizer allows Cross-site Scripting
EPSS 0.37%
Description
Namespace attributes are not encoded correctly during HTML serialization. This allows bypassing the cross-site scripting prevention mechanism of `typo3/html-sanitizer` before version 2.3.2. Credits to Doyensec in collaboration with Claude and Anthropic Research for reporting this vulnerability.
How to fix CVE-2026-47345
To remediate CVE-2026-47345, upgrade the affected package to a fixed version below.
- Packagist/typo3/html-sanitizer—upgrade to 2.3.2 or later
Is CVE-2026-47345 being exploited?
Low — EPSS is 0.4%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 2.3.2
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 4.0 | — | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N |