Vulnerability · Published Sep 10, 2026 · Assigned by mitre
CVE-2026-89087
High 7.3
In plain English
A high-severity security flaw in cstruct from OCaml. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 25% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)7.3High
Exploit odds (30 days)0.3%top 75.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
The cstruct package before 6.3.0 for OCaml mishandles indexes.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | ocaml-cstruct | no fix listed | DEBIAN-CVE-2026-89087 |
| Debian:13 | ocaml-cstruct | no fix listed | DEBIAN-CVE-2026-89087 |
| Debian:14 | ocaml-cstruct | 6.3.0-1 | DEBIAN-CVE-2026-89087 |
| Ubuntu:22.04:LTS | ocaml-cstruct | no fix listed | UBUNTU-CVE-2026-89087 |
| Ubuntu:24.04:LTS | ocaml-cstruct | no fix listed | UBUNTU-CVE-2026-89087 |
| Ubuntu:26.04:LTS | ocaml-cstruct | no fix listed | UBUNTU-CVE-2026-89087 |
| Ubuntu:26.10 | ocaml-cstruct | no fix listed | UBUNTU-CVE-2026-89087 |
Affected products (as reported)
Weakness: CWE-573 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L