CVE-2025-66578

xmlseclibs is a library written in PHP for working with XML Encryption and Signatures. Versions 3.1.3 contain an authentication bypass vulnerability due to a flaw in the libxml2 canonicalization process during document transformation. When libxml2’s canonicalization is invoked on an invalid XML input, it may return an empty string rather than a canonicalized node. xmlseclibs then proceeds to compute the DigestValue over this empty string, treating it as if canonicalization succeeded. This issue is fixed in version 3.1.4. Workarounds include treating canonicalization failures (exceptions or nil/empty outputs) as fatal and aborting validation, and/or adding explicit checks to reject when canonicalize returns nil/empty or raises errors.

CVSS v3 6.0 MEDIUM

6.0^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.2 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/robrichards/xmlseclibs/blob/f4131320c6dcd460f1b0c67f16f8bf24ce4b5c3e/src/XMLSecurityDSig.php#L296	Product
https://github.com/robrichards/xmlseclibs/commit/69fd63080bc47a8d51bc101c30b7cb756862d1d6	Patch
https://github.com/robrichards/xmlseclibs/security/advisories/GHSA-c4cc-x928-vjw9	Vendor Advisory Exploit

Configurations

Configuration 1 (hide)

cpe:2.3:a:xmlseclibs_project:xmlseclibs:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2025-12-09 16:18

Updated : 2025-12-11 16:23

NVD link : CVE-2025-66578

Mitre link : CVE-2025-66578

CVE.ORG link : CVE-2025-66578

JSON object : View

Products Affected

xmlseclibs_project

xmlseclibs

CWE

CWE-248

Uncaught Exception

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