SignXML is an implementation of the W3C XML Signature standard in Python. When verifying signatures with X509 certificate validation turned off and HMAC shared secret set (`signxml.XMLVerifier.verify(require_x509=False, hmac_key=...`), versions of SignXML prior to 4.0.4 are vulnerable to a potential timing attack. The verifier may leak information about the correct HMAC when comparing it with the user supplied hash, allowing users to reconstruct the correct HMAC for any data.
Metrics
Affected Vendors & Products
References
History
Mon, 02 Jun 2025 20:15:00 +0000
Type | Values Removed | Values Added |
---|---|---|
Metrics |
ssvc
|
Mon, 02 Jun 2025 16:45:00 +0000
Type | Values Removed | Values Added |
---|---|---|
Description | SignXML is an implementation of the W3C XML Signature standard in Python. When verifying signatures with X509 certificate validation turned off and HMAC shared secret set (`signxml.XMLVerifier.verify(require_x509=False, hmac_key=...`), versions of SignXML prior to 4.0.4 are vulnerable to a potential timing attack. The verifier may leak information about the correct HMAC when comparing it with the user supplied hash, allowing users to reconstruct the correct HMAC for any data. | |
Title | SignXML's signature verification with HMAC is vulnerable to a timing attack | |
Weaknesses | CWE-208 | |
References |
| |
Metrics |
cvssV4_0
|

Status: PUBLISHED
Assigner: GitHub_M
Published: 2025-06-02T16:23:27.706Z
Updated: 2025-06-02T16:41:13.270Z
Reserved: 2025-05-29T16:34:07.174Z
Link: CVE-2025-48995

Updated: 2025-06-02T16:41:06.346Z

Status : Awaiting Analysis
Published: 2025-06-02T17:15:41.063
Modified: 2025-06-02T17:32:17.397
Link: CVE-2025-48995

No data.