Vulnerability · Published Mar 29, 2026 · Assigned by CPANSec
CVE-2026-4176Perl versions from 5.9.4 before 5.40.4-RC1, from 5.41.0 before 5.42.2-RC1, from 5.43.0 before 5.43.9 contain a vulnerable version of Compress::Raw::Zlib
Critical 9.8
In plain English
A critical-severity security flaw in perl from SHAY. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 55% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Perl versions from 5.9.4 before 5.40.4-RC1, from 5.41.0 before 5.42.2-RC1, from 5.43.0 before 5.43.9 contain a vulnerable version of Compress::Raw::Zlib. Compress::Raw::Zlib is included in the Perl package as a dual-life core module, and is vulnerable to CVE-2026-3381 due to a vendored version of zlib which has several vulnerabilities, including CVE-2026-27171. The bundled Compress::Raw::Zlib was updated to version 2.221 in Perl blead commit c75ae9cc164205e1b6d6dbd57bd2c65c8593fe94.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.24 | perl | 5.42.2-r0 | ALPINE-CVE-2026-4176 |
| Debian:12 | perl | 5.10.0-21 | DEBIAN-CVE-2026-4176 |
| Debian:13 | perl | 5.10.0-21 | DEBIAN-CVE-2026-4176 |
| Debian:14 | perl | 5.10.0-21 | DEBIAN-CVE-2026-4176 |
Affected products (as reported)
Weakness: CWE-1395 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
References
- https://www.cve.org/CVERecord?id=CVE-2026-3381 vendor-advisory, related, vdb-entry
- https://lists.security.metacpan.org/cve-announce/msg/37638919/ vendor-advisory
- https://github.com/Perl/perl5/commit/c75ae9cc164205e1b6d6dbd57bd2c65c8593fe94 patch
- https://metacpan.org/release/PMQS/Compress-Raw-Zlib-2.221/source/Changes release-notes
- https://metacpan.org/release/SHAY/perl-5.40.4/changes release-notes
- https://metacpan.org/release/SHAY/perl-5.42.2/changes release-notes
- http://www.openwall.com/lists/oss-security/2026/03/30/2