CVE-2025-40934

CRITICAL
Published Nov 26, 2025 Modified Dec 30, 2025 CWE-347

Description

XML-Sig versions 0.27 through 0.67 for Perl incorrectly validates XML files if signatures are omitted. An attacker can remove the signature from the XML document to make it pass the verification check. XML-Sig is a Perl module to validate signatures on XML files.  An unsigned XML file should return an error message.  The affected versions return true when attempting to validate an XML file that contains no signatures.

CVSS v3.1 Score

9.3
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N

Weakness Type (CWE)

CWE-347 CWE-347

Affected Products

Vendor Product
xml\ \

References

Frequently Asked Questions

What is CVE-2025-40934? +
XML-Sig versions 0.27 through 0.67 for Perl incorrectly validates XML files if signatures are omitted. An attacker can remove the signature from the XML document to make it pass the verification check. XML-Sig is a Perl module to validate signatures on XML files.  An unsigned XML file should return an error message.  The affected versions return true when attempting to validate an XML file that contains no signatures. It has a CVSS v3.1 base score of 9.3 (CRITICAL).
How severe is CVE-2025-40934? +
CVE-2025-40934 has a CVSS v3.1 score of 9.3 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.
What products are affected by CVE-2025-40934? +
CVE-2025-40934 affects products from xml\, specifically: \. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2025-40934? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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