CVE-2026-89087

Index Out‑of‑Bounds Vulnerability in OCaml cstruct

Published Sep 10, 2026 CVSS 3.1 · 7.3 High EPSS < 1% KEV · Not listed
Description
The cstruct package before 6.3.0 for OCaml mishandles indexes.

Analysis

AI-generated

Technical impact

The cstruct package for OCaml before version 6.3.0 contains a flaw that mishandles indexes, allowing untrusted data to exceed expected bounds. This weakness can lead to memory corruption, potentially allowing an attacker to corrupt data structures or trigger a crash, thereby affecting confidentiality, integrity, or availability of the affected application. The identified weakness aligns with CWE-573, which describes scenarios where input data is not properly validated as a buffer offset.

Affected Systems

OCaml cstruct libraries with versions prior to 6.3.0 are vulnerable. Systems that compile or link against these older releases may be at risk if they process untrusted input that includes out‑of‑range indexes. Precise product or version details beyond the stated 6.3.0 cutoff are not provided in the advisory.

Risk and Exploitability

The CVSS score of 7.3 indicates a high severity vulnerability. No EPSS score is CISA KEV catalog. Exploitation would require an attacker to supply crafted input that triggers the out‑of‑bounds operation; the exact attack vector and conditions are not detailed, so the risk assessment relies on the high CVSS score and the potential for memory corruption.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Upgrade OCaml cstruct to version 6.3.0 or newer
  • Add explicit bounds checking for indices before they are used with cstruct to prevent out-of-range access
  • Ensure that any untrusted input is validated or sanitized prior to being processed by cstruct to reduce risk of exploitation

Generated by OpenCVE AI on September 10, 2026 at 23:14 UTC.

Tracking

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Advisories

No advisories available
References
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Ocaml
Ocaml cstruct
Vendors & Products Ocaml
Ocaml cstruct
Type Values Removed Values Added
Title Index Out‑of‑Bounds Vulnerability in OCaml cstruct
Type Values Removed Values Added
Description The cstruct package before 6.3.0 for OCaml mishandles indexes.
Weaknesses CWE-573
References
Metrics cvssV3_1

{'score': 7.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L'}

Weaknesses
  • CWE-573

    Improper Following of Specification by Caller

Sources

Status
PUBLISHED
Assigner
mitre
Published
Updated
Sep 14, 2026, 3:41 PM
Reserved
Sep 10, 2026, 7:55 PM
Status
Deferred
Published
Sep 10, 2026, 8:17 PM
Modified
Sep 22, 2026, 8:00 PM