CVE-2026-28364: In OCaml before 4.14.3 and 5.x before 5.4.1, a buffer over-read in Marshal deserialization (runtime/intern.c) enables remote code execution through a multi-phase attack chain. The vulnerability stems from missing bounds validation in the readblock() function, which performs unbounded memcpy() operations using attacker-controlled lengths from crafted Marshal data.

Overview

Severity

High (CVSS 7.9)

CVSS Vector

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

Exploit Status

Not Exploited

Patch Tuesday

2026-Feb

Released

2026-02-28

Last Updated

2026-03-11

EPSS Score

0.04% (percentile: 13.3%)

Affected Products (2)

Other

• 20930-17084
• 21039-17086

Revision History

• 2026-02-28: Information published.
• 2026-03-08: Information published.
• 2026-03-09: Information published.
• 2026-03-11: Information published.