CVE-2025-48995 – signxml

Package

Manager: pip
Name: signxml
Vulnerable Version: >=0 <4.0.4

Severity

Level: Medium

CVSS v3.1: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:P/RL:O/RC:C

CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

EPSS: 0.00036 pctl0.08985

Details

SignXML's signature verification with HMAC is vulnerable to a timing attack When verifying signatures with X509 certificate validation turned off and HMAC shared secret set (`signxml.XMLVerifier.verify(require_x509=False, hmac_key=...`), prior versions of SignXML 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.

Metadata

Created: 2025-06-05T00:37:19Z
Modified: 2025-06-05T00:37:19Z
Source: https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2025/06/GHSA-gmhf-gg8w-jw42/GHSA-gmhf-gg8w-jw42.json
CWE IDs: ["CWE-208"]
Alternative ID: GHSA-gmhf-gg8w-jw42
Finding: F063
Auto approve: 1