CVE-2025-40909
Perl threads have a working directory race condition where file operations may target unintended paths
Vexday Risk Score
13Low
SSVC decision (CISA)
Track
No exploitation signal → monitor
CVSS 5.9EPSS 0.4%KEV nãoPoC —Nuclei —Metasploit —Patch referenciado
Lifecycle
30 May 2025Published on NVD
Recommendation: Monitor — no exploitation signal at the moment.
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
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Affected products
perl · perlWant to know if your infrastructure is exposed to this?
Talk to TrueHacking →References
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1098226http://seclists.org/fulldisclosure/2025/Sep/53http://seclists.org/fulldisclosure/2025/Sep/54http://seclists.org/fulldisclosure/2025/Sep/55https://github.com/Perl/perl5/commit/11a11ecf4bea72b17d250cfb43c897be1341861ehttps://github.com/Perl/perl5/commit/918bfff86ca8d6d4e4ec5b30994451e0bd74aba9.patchhttps://github.com/Perl/perl5/issues/10387https://github.com/Perl/perl5/issues/23010https://lists.debian.org/debian-lts-announce/2026/04/msg00018.htmlhttps://perldoc.perl.org/5.14.0/perl5136delta#Directory-handles-not-copied-to-threadshttps://www.openwall.com/lists/oss-security/2025/05/22/2http://www.openwall.com/lists/oss-security/2025/05/23/1