# CVE-2026-12087

## Summary

- **CVE ID:** CVE-2026-12087
- **Severity:** CRITICAL
- **CVSS Score:** 9.1 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H)
- **CWE:** CWE-125, CWE-805
- **Published:** Jun 15, 2026
- **Last Modified:** Jun 16, 2026

## Description

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.

## Affected Products

- PEVANS — Socket (0)

## References

- [CNA](https://metacpan.org/release/PEVANS/Socket-2.041/changes)
- [CNA](https://github.com/Perl/perl5/commit/de19a0b0ad1900fef976c5c1400bd8f11ec6c6cb.patch)
- [CVE](http://www.openwall.com/lists/oss-security/2026/06/15/10)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 0.37%
- **EPSS Percentile:** 30.8

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-11._