CVE-2025-40909

Publication date 30 May 2025

Last updated 4 November 2026

Ubuntu priority

Medium

Why this priority?

Cvss 3 Severity Score

5.9 · Medium

Score breakdown

Description

Perl threads have a working directory race condition where file operations may target unintended paths. If a directory handle is open at thread creation, the process-wide current working directory is temporarily changed in order to clone that handle for the new thread, which is visible from any third (or more) thread already running. This may lead to unintended operations such as loading code or accessing files from unexpected locations, which a local attacker may be able to exploit. The bug was introduced in commit 11a11ecf4bea72b17d250cfb43c897be1341861e and released in Perl version 5.13.6

Status

Package Ubuntu Release Status
perl 26.10 stonking
Not affected
26.04 LTS resolute
Not affected
25.10 questing
Not affected
25.04 plucky
Fixed in 5.40.1-2ubuntu0.2
24.10 oracular Ignored end of life, was needs-triage
24.04 LTS noble
Fixed in 5.38.2-3.2ubuntu0.2
22.04 LTS jammy
Fixed in 5.34.0-3ubuntu1.5
20.04 LTS focal
Vulnerable
18.04 LTS bionic
Vulnerable
16.04 LTS xenial
Vulnerable
14.04 LTS trusty
Vulnerable

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
perl

Severity score breakdown

CVSS version: CVSS v3.0

Base score 5.9 · Medium

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

References

Related Ubuntu Security Notices (USN)

Other references

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