CVE-2026-12087 | Socket versions before 2.041 for Perl have an out-of-bounds heap read

Socket versions before 2.041 for Perl have an out-of-bounds heap read. In Socket.xs, pack_ip_mreq_source() checks the length of its source argument before the argument is read, so the check tests the byte length carried over from the preceding multiaddr argument instead. Both addresses occupy a 4-byte field, so a valid multiaddr lets a source of any length pass the check, and the source is then copied into the 4-byte imr_sourceaddr field with a fixed-size copy. A source shorter than 4 bytes is not rejected, and the copy reads up to 3 bytes past the end of its buffer. Calling pack_ip_mreq_source() with a source value shorter than 4 bytes copies adjacent heap memory into the returned packed structure.

Published: 2026-06-15 Last update: 2026-06-17 Assigner: 9b29abf9-4ab0-4765-b253-1875cd9b441e Source: 9b29abf9-4ab0-4765-b253-1875cd9b441e
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-12087 is rated Moderate Risk (47.5/100): CVSS Critical severity, with low exploitation likelihood (EPSS 0.39%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-12087

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-17 0.19% 0.39% +0.21%
2 2026-06-16 — 0.19% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-12087

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.1 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.2 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2026-12087

GitHub Security Advisory for CVE-2026-12087

GHSA-q5cv-5vf6-95gp · Severity: critical — Socket versions before 2.041 for Perl have an out-of-bounds heap read. In Socket.xs,...

OS Trackers for CVE-2026-12087

vendor priority summary link
debian not yet assigned CVE-2026-12087 not yet assigned priority: Debian including 2 source packages (libsocket-perl, perl), 10 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): open 8, resolved 2. https://security-tracker.debian.org/tracker/CVE-2026-12087
redhat medium — https://access.redhat.com/security/cve/CVE-2026-12087
suse medium — https://www.suse.com/security/cve/CVE-2026-12087/
ubuntu medium CVE-2026-12087 medium priority: Ubuntu including 2 source packages (libsocket-perl, perl), 16 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): needs-triage 15, released 1. https://ubuntu.com/security/CVE-2026-12087

Affected software / configurations for CVE-2026-12087

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-12087

cvelogic Threat Intelligence