CVE-2026-4176
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.73%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.73% probability · 52th percentile
- CISA KEV
- Not listed
- Affected
- perl/perl
- Source
- 9b29abf9-4ab0-4765-b253-1875cd9b441e
References
- https://github.com/Perl/perl5/commit/c75ae9cc164205e1b6d6dbd57bd2c65c8593fe94Patch
- https://lists.security.metacpan.org/cve-announce/msg/37638919/Third Party Advisory
- https://metacpan.org/release/PMQS/Compress-Raw-Zlib-2.221/source/ChangesRelease Notes
- https://metacpan.org/release/SHAY/perl-5.40.4/changesRelease Notes
- https://metacpan.org/release/SHAY/perl-5.42.2/changesRelease Notes
- https://www.cve.org/CVERecord?id=CVE-2026-3381Third Party Advisory
- http://www.openwall.com/lists/oss-security/2026/03/30/2Mailing List, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.