CVE-2025-40908

Name: CVE-2025-40908
Creator: NVD / NIST
Published: 2025-06-01T14:15:21.113+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.1/10EPSS 0.37%

Last modified Jun 17, 2026

CVE-2025-40908 is a critical-severity vulnerability rated 9.1/10 on the CVSS scale. YAML-LibYAML prior to 0.903.0 for Perl uses 2-args open, allowing existing files to be modified. EPSS estimates a 0.37% chance of exploitation in the next 30 days.

Description

YAML-LibYAML prior to 0.903.0 for Perl uses 2-args open, allowing existing files to be modified

Metrics

CVSS 3.1

9.1/10

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

EPSS Probability

0.37%

28.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-552

Affected Software

Vendor	Product	Versions
Ingydotnet	Yaml-Libyaml	< 0.903.0

References

https://github.com/ingydotnet/yaml-libyaml-pm/issues/120Exploit, Issue Tracking
https://github.com/ingydotnet/yaml-libyaml-pm/pull/121Issue Tracking, Patch
https://github.com/ingydotnet/yaml-libyaml-pm/pull/122Issue Tracking, Patch

Timeline

Published: Jun 1, 2025
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2025-40908?

YAML-LibYAML prior to 0.903.0 for Perl uses 2-args open, allowing existing files to be modified

How severe is CVE-2025-40908?

CVE-2025-40908 has a CVSS score of 9.1/10 (CRITICAL severity). The EPSS model estimates a 0.37% probability of exploitation in the next 30 days.

How do I fix CVE-2025-40908?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2025-40908?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST