High (7.8) in ocaml ocaml. EPSS 0.2% chance of exploitation in the next 30 days.
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.
Severity
CVSS 3.1
7.8 high
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
0.2% chance of exploitation in the next 30 days; higher than 15% of CVEs (scores of 2026-10-31)