Critical severity · published Mar 29, 2026
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
9.8
CVSS
0.7%
EPSS
No
On KEV
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 vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.7% · higher than 54% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PE
perl · SHAY
5.9.4 before 5.40.4-RC1; 5.41.0 before 5.42.2-RC1; 5.43.0 before 5.43.9 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-4176
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-4176
Patch
https://github.com/Perl/perl5/commit/c75ae9cc164205e1b6d6dbd57bd2c65c8593fe94
Third Party Advisory
https://lists.security.metacpan.org/cve-announce/msg/37638919/
Release Notes
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
Third Party Advisory
https://www.cve.org/CVERecord?id=CVE-2026-3381