Out-of-bounds Read in Ocaml
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.
EPSS: 0.002 (11.4th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.9 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N.
Affected products
- Ocaml — versions 0, 5.0.0
Weakness classification (CWE)
References
- cve@mitre.org (Vendor Advisory)
- cve@mitre.org (Third Party Advisory)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2026-28364?
- CVE-2026-28364 is a high-severity vulnerability in Ocaml, classified under Buffer Over-read. CVSS score: 7.9/10. Published 2026-02-27.
- How severe is CVE-2026-28364?
- High severity. CVSS v3 base score is 7.9 out of 10.