VulnerabilityAnalyzed
CVE-2026-25543
HtmlSanitizer is a .NET library for cleaning HTML fragments and documents from constructs that can lead to XSS attacks.
MEDIUM 6.3EPSS 0.25%
Does this matter?
Lower severity and a low EPSS score (0.25%). Track it; it rarely justifies an emergency change on its own.
Description
HtmlSanitizer is a .NET library for cleaning HTML fragments and documents from constructs that can lead to XSS attacks. Prior to versions 9.0.892 and 9.1.893-beta, if the template tag is allowed, its contents are not sanitized. The template tag is a special tag that does not usually render its contents, unless the shadowrootmode attribute is set to open or closed. This issue has been patched in versions 9.0.892 and 9.1.893-beta.
- CVSS 4.0
- 6.3 MEDIUMCVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.25% probability · 16th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-116, CWE-79
- Affected
- htmlsanitizer project/htmlsanitizer
- Source
- security-advisories@github.com
References
- https://github.com/mganss/HtmlSanitizer/commit/0ac53dca30ddad963f2b243669a5066933d82b81Patch
- https://github.com/mganss/HtmlSanitizer/security/advisories/GHSA-j92c-7v7g-gj3fMitigation, Patch, Vendor Advisory
- https://www.nuget.org/packages/HtmlSanitizer/9.0.892Product, Release Notes
- https://www.nuget.org/packages/HtmlSanitizer/9.1.893-betaProduct, Release Notes
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.