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 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 v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/simplesamlphp/saml2/commit/0043033891fdba9618386ab583e1d8afdf8aea6e
https://github.com/simplesamlphp/saml2/commit/6695eb923da491f716009c2a26b34a463ac05c6b
https://github.com/simplesamlphp/saml2/security/advisories/GHSA-5cjr-mxj5-wmrx

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-19 15:17

Updated : 2026-08-19 18:16

NVD link : CVE-2026-49289

Mitre link : CVE-2026-49289

CVE.ORG link : CVE-2026-49289

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

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