CVE-2026-49289: The SimpleSAMLphp SAML2 library is a PHP library for SAML2 related functionality. In 4.19.2 and 4.20.2, the library permits attacker-controlled XPath…

PriorityP349high7.5CVSS 3.1

AVNACLPRNUINSUCNINAH

EPSS

0.78%

55.6th percentile

The SimpleSAMLphp SAML2 library is a PHP library for SAML2 related functionality. In 4.19.2 and 4.20.2, the library permits attacker-controlled XPath transforms while processing XML signatures in specially crafted SAML messages. XPath evaluation can consume uncontrolled processing resources, allowing a remote unauthenticated attacker to deny service to any entity relying on SimpleSAMLphp or directly on the SAML2 library. The mitigation limits the number of transforms, permits only transform algorithms identified by the SAML 2.0 Core specification, and specifically rejects XPath transforms. This issue is fixed in versions 4.19.3 and 4.20.3.

Affected

4 ranges

Vendor	Product	Version range	Fixed in
simplesamlphp	saml2	—	—
simplesamlphp	saml2	—	—
simplesamlphp	saml2	>= 0 < 4.20.3	4.20.3
simplesamlphp	saml2-legacy	>= 0 < 4.20.3	4.20.3

Stop checking back — get the weekly exploitation signal.

Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.