ZDF
Sign inSign up

Vulnerabilities

Security incident · CVE-2025-48995

SignXML is an implementation of the W3C XML Signature standard in Python.

Published Jun 2, 2025 · catalog updated Jun 2, 2025 · XML-Security

Check if you run it

No confirmed exploitation is on record for CVE-2025-48995. EPSS is 0.23%. Act only if a listed version of XML-Security is installed.

Gaps on this record

  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
Medium6.9
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.23%
Remediation
Version ranges on file
Affected products
vendor XML-Security signxml < 4.0.4

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 ( ), 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.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • vendor XML-Security signxml < 4.0.4< 4.0.4

How to fix CVE-2025-48995

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2025-48995. EPSS is 0.23%. Act only if a listed version of XML-Security is installed.

Which versions are affected?

Compare what you have installed with XML-Security signxml < 4.0.4 < 4.0.4. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

No weakness class is stored. EPSS 0.23%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Jun 2, 2025 · EUVD

    Detected

    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 ( ), 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 correc

  2. Jun 2, 2025 · EUVD

    Updated

    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 ( ), 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 correc

Sources

  • CVE.orgVulnerability recordCVE-2025-48995

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2025-48995

    30-day exploitation probability 0.2%

    first.org
  • EUVDVulnerability recordEUVD-2025-16676

    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 ( ), versions of SignXML prior to 4.0.4 are vulnerable to a potential timing attack. The verifier may leak in

    euvd.enisa.europa.eu

References

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.