CVE-2026-101019

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.

• https://my.f5.com/manage/s/article/K000162615

• HIGHCVE-2026-100351PoC
• MEDIUMCVE-2026-106430
• HIGHCVE-2026-106505PoC
• MEDIUMCVE-2026-107825PoC
• MEDIUMCVE-2026-107835PoC
• HIGHCVE-2026-109331PoC
• HIGHCVE-2026-109428PoC
• HIGHCVE-2026-109429PoC

Related by shared AI tags and CWE weakness class. Browse the full archive.