CVE-2026-15534 Affecting perl package, versions *
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
Do your applications use this vulnerable package?
In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.
Test your applications- Snyk IDSNYK-DEBIANUNSTABLE-PERL-18600689
- published10 Aug 2026
- disclosed9 Aug 2026
Introduced: 9 Aug 2026
NewCVE-2026-15534 (opens in a new tab)How to fix?
There is no fixed version for Debian:unstable perl.
NVD Description
Note: Versions mentioned in the description apply only to the upstream perl package and not the perl package as distributed by Debian.
See How to fix? for Debian:unstable relevant fixed versions and status.
Perl versions through 5.45.1 have out-of-bounds heap reads and writes during regular expression matching via an undersized superlinear cache in S_regmatch.
The regex engine's superlinear cache holds one bit per subject position for each participating WHILEM node, so the bit count is the subject length plus one times the number of nodes. Nothing checks that product for positive overflow of the signed 32-bit count: a 286331153 byte subject matched against a pattern with 15 participating nodes stores the count as 14, leaving a two byte cache. The cache is then indexed from the real match position and node number, so reads go past the end of the allocation, and on failure CACHEsayNO sets a bit past it.
A caller that matches an attacker controlled subject of this size against a pattern of this shape can crash the process or corrupt heap memory.
References
- https://security-tracker.debian.org/tracker/CVE-2026-15534
- https://github.com/Perl/perl5/commit/54cf3d44cbbedd17d774e9a37921963e8fd5d0cb.patch
- https://github.com/Perl/perl5/commit/568e6fd238867bb9e99fa3f47cba3169009239e0.patch
- http://www.openwall.com/lists/oss-security/2026/08/09/12
- http://www.openwall.com/lists/oss-security/2026/08/09/13