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.
CVE-2025-48995
This medium-severity CVE scores 6.9 under NVD CVSS v3. EPSS exploit probability: 0.2%, top 52% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 6.9
- EG Score
- 6.9(medium)
- EPSS
- 10.0%
- KEV
- Not listed
Published
June 2, 2025
Last Modified
April 15, 2026
References (2)
- security-advisories@githubhttps://github.com/XML-Security/signxml/commit/1b501faaacf34cf978a52dbc6915ec11e27611cd
- security-advisories@githubhttps://github.com/XML-Security/signxml/security/advisories/GHSA-gmhf-gg8w-jw42
Affected Packages
(1 across 1 ecosystem)
PyPI(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| signxml | 0.0.1 ... 4.0.3 (77 versions) | 4.0.4 | — |
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 9× in last 7d / 46× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
Showing the most recent 100 of 125 total refreshes for this CVE.
- 2026-07-22 14:07 UTCEPSS rescore
- 2026-07-22 14:07 UTCEPSS rescore
- 2026-07-21 15:24 UTCEPSS rescore
- 2026-07-20 17:07 UTCEPSS rescore
- 2026-07-19 14:30 UTCEPSS rescore
- 2026-07-19 14:30 UTCEPSS rescore
- 2026-07-18 10:04 UTCEPSS rescore
- 2026-07-16 17:02 UTCEPSS rescore
- 2026-07-16 17:02 UTCEPSS rescore
- 2026-07-15 01:59 UTCEPSS rescore
- 2026-07-15 01:59 UTCEPSS rescore
- 2026-07-14 07:25 UTCOSV refresh
- 2026-07-13 22:29 UTCEPSS rescore
- 2026-07-13 22:29 UTCEPSS rescore
- 2026-07-13 06:12 UTCEPSS rescore
- 2026-07-12 05:46 UTCEPSS rescore
- 2026-07-11 08:27 UTCEPSS rescore
- 2026-07-11 08:27 UTCEPSS rescore
- 2026-07-09 19:09 UTCEPSS rescore
- 2026-07-09 19:09 UTCEPSS rescore
- 2026-07-08 15:15 UTCEPSS rescore
- 2026-07-07 13:45 UTCEPSS rescore
- 2026-07-06 16:27 UTCEPSS rescore
- 2026-07-06 16:27 UTCEPSS rescore
- 2026-07-06 02:23 UTCEPSS rescore
Show 75 moreShow fewer
- 2026-07-06 02:23 UTCEPSS rescore
- 2026-07-05 02:30 UTCEPSS rescore
- 2026-07-04 06:30 UTCEPSS rescore
- 2026-07-02 17:01 UTCEPSS rescore
- 2026-07-01 15:06 UTCEPSS rescore
- 2026-06-30 23:22 UTCEPSS rescore
- 2026-06-30 23:22 UTCEPSS rescore
- 2026-06-29 14:06 UTCEPSS rescore
- 2026-06-29 14:06 UTCEPSS rescore
- 2026-06-28 14:07 UTCEPSS rescore
- 2026-06-28 14:07 UTCEPSS rescore
- 2026-06-28 04:55 UTCEPSS rescore
- 2026-06-28 04:55 UTCEPSS rescore
- 2026-06-27 03:08 UTCEPSS rescore
- 2026-06-26 05:16 UTCOSV refresh
- 2026-06-25 13:49 UTCEPSS rescore
- 2026-06-25 13:49 UTCEPSS rescore
- 2026-06-24 14:04 UTCEPSS rescore
- 2026-06-24 14:04 UTCEPSS rescore
- 2026-06-23 21:32 UTCEPSS rescore
- 2026-06-23 21:32 UTCEPSS rescore
- 2026-06-22 14:25 UTCEPSS rescore
- 2026-06-22 14:25 UTCEPSS rescore
- 2026-06-21 14:56 UTCEPSS rescore
- 2026-06-21 14:56 UTCEPSS rescore
- 2026-06-21 01:59 UTCEPSS rescore
- 2026-06-21 01:59 UTCEPSS rescore
- 2026-06-19 19:25 UTCEPSS rescore
- 2026-06-19 19:25 UTCEPSS rescore
- 2026-06-18 17:52 UTCEPSS rescore
- 2026-06-18 17:52 UTCEPSS rescore
- 2026-06-17 17:52 UTCEPSS rescore
- 2026-06-17 17:52 UTCEPSS rescore
- 2026-06-16 17:52 UTCEPSS rescore
- 2026-06-16 17:52 UTCEPSS rescore
- 2026-06-15 17:48 UTCEPSS rescore
- 2026-06-14 23:17 UTCEPSS rescore
- 2026-06-13 23:00 UTCEPSS rescore
- 2026-06-12 23:11 UTCEPSS rescore
- 2026-06-11 14:00 UTCEPSS rescore
- 2026-06-11 14:00 UTCEPSS rescore
- 2026-06-10 22:18 UTCEPSS rescore
- 2026-06-10 22:18 UTCEPSS rescore
- 2026-06-10 13:22 UTCEPSS rescore
- 2026-06-08 16:09 UTCEG score recompute▲ 6.90
- 2026-06-08 14:16 UTCEPSS rescore
- 2026-06-08 14:16 UTCEPSS rescore
- 2026-06-07 15:24 UTCEPSS rescore
- 2026-06-06 13:47 UTCEPSS rescore
- 2026-06-06 13:47 UTCEPSS rescore
- 2026-06-05 22:46 UTCEPSS rescore
- 2026-06-05 22:46 UTCEPSS rescore
- 2026-06-05 06:10 UTCEPSS rescore
- 2026-06-05 06:10 UTCEPSS rescore
- 2026-06-04 13:12 UTCEPSS rescore
- 2026-06-04 13:12 UTCEPSS rescore
- 2026-06-03 05:40 UTCOSV refresh
- 2026-06-02 20:12 UTCEPSS rescore
- 2026-06-02 20:12 UTCEPSS rescore
- 2026-06-01 13:51 UTCEPSS rescore
- 2026-06-01 13:51 UTCEPSS rescore
- 2026-05-31 22:30 UTCEPSS rescore
- 2026-05-31 22:30 UTCEPSS rescore
- 2026-05-31 00:16 UTCEPSS rescore
- 2026-05-31 00:16 UTCEPSS rescore
- 2026-05-29 13:44 UTCEPSS rescore
- 2026-05-28 13:44 UTCEPSS rescore
- 2026-05-28 13:44 UTCEPSS rescore
- 2026-05-28 13:44 UTCEPSS rescore
- 2026-05-28 13:44 UTCEPSS rescore
- 2026-05-27 13:40 UTCEPSS rescore
- 2026-05-27 13:40 UTCEPSS rescore
- 2026-05-27 13:40 UTCEPSS rescore
- 2026-05-27 13:40 UTCEPSS rescore
- 2026-05-26 13:44 UTCEPSS rescore
Related CVEs(same CWE)
Frequently asked(5)
What is CVE-2025-48995?
When was CVE-2025-48995 disclosed?
Is CVE-2025-48995 actively exploited?
What is the CVSS score of CVE-2025-48995?
How do I remediate CVE-2025-48995?
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2025-48995
Is Your Infrastructure Affected by CVE-2025-48995?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.