CVE-2026-104828
HtmlUnit Neko is an HtmlUnit adaptation of NekoHTML
- Risk score
- 52/100
- CVSS
- 7.2 v3.1
- Exploit chance (30 days)
- 0.3%
- Published
- 15 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- HtmlUnit Neko is an HtmlUnit adaptation of NekoHTML. Prior to 5.4.0, HTMLWriterFilter writes decoded TEXTAREA and TITLE character content without entity encoding because both elements are treated as special content. During a parse-and-serialize round trip, entity references inside these escapable raw-text elements are…
- Affected
- See advisory
- Fix
- Upgrade the product to 5.4.0 or later.
- Exploitation
- No known exploitation
Why it is Yellow
- CVSS 7.2 high
- Remotely exploitable without logging in
References
- https://github.com/HtmlUnit/htmlunit-neko/commit/c165891e0753aef3e05f5daa6250d3e8d4ada3c0
- https://github.com/HtmlUnit/htmlunit-neko/releases/tag/5.4.0
- https://github.com/HtmlUnit/htmlunit-neko/security/advisories/GHSA-39xg-prhf-8785
- https://github.com/HtmlUnit/htmlunit-neko/security/advisories/GHSA-39xg-prhf-8785
Original description
HtmlUnit Neko is an HtmlUnit adaptation of NekoHTML. Prior to 5.4.0, HTMLWriterFilter writes decoded TEXTAREA and TITLE character content without entity encoding because both elements are treated as special content. During a parse-and-serialize round trip, entity references inside these escapable raw-text elements are decoded by the parser and then emitted as raw markup by printCharacters(), changing the document's semantics. Applications that use htmlunit-neko in an HTML sanitizer, content filter, or other parse-transform-serialize pipeline can therefore turn attacker-controlled encoded text into executable markup when the output is rendered by a browser. This issue is fixed in version 5.4.0.
Last activity 15 Oct 2026. Patch Forecast updates every hour.