[ CVE-2026-105219 · Published 4 Oct 2026 ]
Vulnerability in mwilliamson mammoth.js
CVSS 7.5
EPSS <1%No fix listed yet
[ Description ]Official description
Mammoth.js 1.3.0 before 1.12.3 contains a regular expression denial of service vulnerability in the style map tokeniser in lib/styles/parser/tokeniser.js due to overlapping regex alternatives. Attackers can supply a crafted .docx with an unterminated quoted string of repeated backslash escapes in mammoth/style-map to block the Node.js event loop.
[ Fixes ]Fixes and patches
No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.
[ References ]References
- github.com/mwilliamson/mammoth.js
- github.com/mwilliamson/mammoth.js/blob/1.12.2/lib/styles/parser/tokeniser.js
- github.com/mwilliamson/mammoth.js/commit/dc49225425c2c07de0a6dc3529f2386c82a032b4
- github.com/mwilliamson/mammoth.js/issues/487
- www.vulncheck.com/advisories/mammoth-js-1.3.0-before-1.12.3-redos-via-style-map-tokeniser