CVE-2026-49289 — HIGH (7.5)

Vulnerability Description

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.

CVSS Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

NONE

Integrity

NONE

Availability

HIGH

Related Weaknesses (CWE)

CWE-400

References

FAQ

What is CVE-2026-49289?

CVE-2026-49289 is a vulnerability with a CVSS score of 7.5 (HIGH). 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 spec...

How severe is CVE-2026-49289?

CVE-2026-49289 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-49289?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.