High
ocaml — security advisory
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.
- Products
- ocaml
- Affected versions
- 3.12.1-4ubuntu1, 4.01.0-3ubuntu2, 4.01.0-3ubuntu3, 4.01.0-3ubuntu3.1, 4.01.0-3ubuntu3.1+esm1, 4.01.0-4ubuntu1, 4.02.3-5ubuntu1, 4.02.3-5ubuntu2, 4.02.3-5ubuntu2+esm1, 4.04.0-2ubuntu4, 4.05.0-10ubuntu1, 4.05.0-10ubuntu1+esm1, 4.05.0-12ubuntu3, 4.08.1-8, 4.11.1-4, 4.11.1-5ubuntu1, 4.13.1-3ubuntu1, 4.13.1-6ubuntu1, 4.14.1-1ubuntu1, 5.3.0-2, 5.3.0-3, 5.4.0-1ubuntu1, 5.4.0-2ubuntu1, 5.4.0-3ubuntu1, 5.4.1-1ubuntu1
- Fixed versions
- Not specified
- CVEs
- CVE-2026-28364
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 17:19 UTC · Revision 1
Source evidence
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.
osv:UBUNTU-CVE-2026-28364
ocaml
Fixed versions: Not specified
ocaml
Fixed versions: Not specified
ocaml
Fixed versions: Not specified
ocaml
Fixed versions: Not specified
ocaml
Fixed versions: Not specified
ocaml
Fixed versions: Not specified
ocaml
Fixed versions: Not specified
ocaml
Fixed versions: Not specified
ocaml
Fixed versions: Not specified
Complete source record
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"modified": "2026-10-27T04:17:55.351202032Z",
"provider": "osv",
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"references": [
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"https://www.cve.org/CVERecord?id=CVE-2026-28364",
"https://osv.dev/vulnerability/OSEC-2026-01",
"https://github.com/ocaml/security-advisories/blob/generated-osv/2026/OSEC-2026-01.json"
]
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},
"source_id": "core-osv",
"document_id": 460326,
"published_at": "2026-02-27T04:16:00+00:00"
}