CVE-2026-101019

CVE-2026-101019 · NGINX ngx_http_js_module vulnerability

This page contains facts from public vulnerability sources. Check the original advisory before updating.

Description NGINX JavaScript (njs) has a vulnerability where the njs XML module exposes entity-backed XML attributes inconsistently with libxml2 canonicalization. In both the built-in njs and QuickJS backends during the canonicalization process, the $attr$Name getter may return undefined for an explicitly present attribute containing an internal entity reference. The $attrs getter may return a value derived only from the first attribute child. This may allow an unauthenticated attacker that invests significant effort in obtaining a genuinely signed document to skip validation while signature verification succeeds. An nginx-saml deployment is a confirmed affected consumer when run with the built-in njs backend. Impact In affected signed-XML consumers, an unauthenticated attacker can cause security-relevant attributes to appear absent or truncated while signature verification succeeds. In nginx-saml, this can bypass expiry, Destination, and request-correlation checks, enabling replay or acceptance of a response outside its intended context. It does not permit signature or identity forgery, or a direct availability impact. There is no control plane exposure; this is a data plane issue only.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

CVSS 8.3 · High · EPSS 0.2% · Fix available

Published

2026-10-14T14:40:29.685Z

Updated

2026-10-15T16:43:46.354Z

Stack: system

Check your server →