CVE-2025-40934 | XML-Sig prior to 0.68 for Perl improperly validates XML without signatures

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.

Published: 2025-11-26 Last update: 2025-12-30 Assigner: 9b29abf9-4ab0-4765-b253-1875cd9b441e Source: 9b29abf9-4ab0-4765-b253-1875cd9b441e
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-40934 is rated Low Risk (37.7/100): CVSS Critical severity, with low exploitation likelihood (EPSS 0.01%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-40934

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2025-11-27 — 0.01% —

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-40934

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.3 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 4.7 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2025-40934

OS Trackers for CVE-2025-40934

vendor priority summary link
alpine — CVE-2025-40934: 1 source package rows (perl-xml-sig); 3 state rows across 3 repos (3.22-community, 3.23-community, edge-community); fixed 3, open 0. https://security.alpinelinux.org/vuln/CVE-2025-40934

Affected software / configurations for CVE-2025-40934

Vendor Product Version Raw CPE
xml::sig_project xml::sig >= 0.27, <= 0.67 cpe:2.3:a:xml\:\:sig_project:xml\:\:sig:*:*:*:*:*:perl:*:*

References for CVE-2025-40934

cvelogic Threat Intelligence