CVE-2026-4176

# PoC for CVE-2026-4176 # This script demonstrates the usage of Compress::Raw::Zlib with potentially malicious input. # Exploiting the underlying zlib vulnerability (CVE-2026-27171) requires specific byte sequences. use strict; use Compress::Raw::Zlib; # Placeholder for a malicious zlib stream that triggers the buffer overflow. # Actual payload would be derived from the specific zlib vulnerability details. my $payload = "\x78\x9c" . "\x41" x 1000; my ($d, $status) = Compress::Raw::Zlib::Inflate->new() or die "Cannot create inflation stream: $status"; my $output = ''; my $result = $d->inflate($payload, $output); if ($result < 0) { print "Inflation failed or potentially triggered the vulnerability.\n"; } else { print "Inflation successful.\n"; }

{"cve": {"id": "CVE-2026-4176", "sourceIdentifier": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "published": "2026-03-29T21:16:15.717", "lastModified": "2026-04-22T17:31:45.770", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "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.\n\nCompress::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."}, {"lang": "es", "value": "Las versiones de Perl desde la 5.9.4 anteriores a la 5.40.4-RC1, desde la 5.41.0 anteriores a la 5.42.2-RC1, y desde la 5.43.0 anteriores a la 5.43.9 contienen una versión vulnerable de Compress::Raw::Zlib.\n\nCompress::Raw::Zlib está incluido en el paquete de Perl como un módulo central de doble vida, y es vulnerable a CVE-2026-3381 debido a una versión empaquetada de zlib que tiene varias vulnerabilidades, incluyendo CVE-2026-27171. El Compress::Raw::Zlib empaquetado fue actualizado a la versión 2.221 en el commit de Perl blead c75ae9cc164205e1b6d6dbd57bd2c65c8593fe94."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "NVD-CWE-Other"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:perl:perl:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.9.4", "versionEndExcluding": "5.40.4", "matchCriteriaId": "CB7DC630-9F3F-404F-9759-882BFCC79961"}, {"vulnerable": true, "criteria": "cpe:2.3:a:perl:perl:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.41.0", "versionEndExcluding": "5.42.2", "matchCriteriaId": "19F3A1E9-F479-4537-AA41-6800D49A3A68"}, {"vulnerable": true, "criteria": "cpe:2.3:a:perl:perl:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.43.0", "versionEndExcluding": "5.43.9", "matchCriteriaId": "A21CB5D2-7B78-485A-A6E8-5C2BBAE99334"}]}]}], "references": [{"url": "https://github.com/Perl/perl5/commit/c75ae9cc164205e1b6d6dbd57bd2c65c8593fe94", "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "tags": ["Patch"]}, {"url": "https://lists.security.metacpan.org/cve-announce/msg/37638919/", "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "tags": ["Third Party Advisory"]}, {"url": "https://metacpan.org/release/PMQS/Compress-Raw-Zlib-2.221/source/Changes", "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "tags": ["Release Notes"]}, {"url": "https://metacpan.org/release/SHAY/perl-5.40.4/changes", "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "tags": ["Release Notes"]}, {"url": "https://metacpan.org/release/SHAY/perl-5.42.2/changes", "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "tags": ["Release Notes"]}, {"url": "https://www.cve.org/CVERecord?id=CVE-2026-3381", "source": "9b29abf9-4ab0-4765-b253-1875cd9b441e", "tags": ["Third Party Advisory"]}, {"url": "http://www.openwall.com/lists/oss-security/2026/03/30/2", "source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Mailing List", "Third Party Advisory"]}]}}