Strix
26.1K

CVE-2026-12087

CRITICALCVSS 9.1/10EPSS 0.39%

Last modified

CVE-2026-12087 is a critical-severity vulnerability rated 9.1/10 on the CVSS scale. 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. EPSS estimates a 0.39% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1
9.1/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

EPSS Probability
0.39%

30.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

References

Timeline

Published
Last Modified
Status
Deferred

Frequently Asked Questions

What is CVE-2026-12087?
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.
How severe is CVE-2026-12087?
CVE-2026-12087 has a CVSS score of 9.1/10 (CRITICAL severity). The EPSS model estimates a 0.39% probability of exploitation in the next 30 days.
How do I fix CVE-2026-12087?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-12087?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST