What is CVE-2026-34353?

CVE-2026-34353 is a medium-severity vulnerability in Ocaml, classified under Integer Overflow or Wraparound. CVSS score: 5.9/10. Published 2026-03-27.

How severe is CVE-2026-34353?

Medium severity. CVSS v3 base score is 5.9 out of 10.

Integer overflow in Ocaml

CVE-2026-34353

In OCaml through 4.14.3, Bigarray.reshape allows an integer overflow, and resultant reading of arbitrary memory, when untrusted data is processed.

Vulnerability class: Integer Overflow

Published 2026-03-27 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.001 (3.3th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 3rd percentile — 3.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: +0.000

Affected products

Ocaml — versions 0

Weakness classification (CWE)

CWE-190 — Integer Overflow or Wraparound

References

github.com/ocaml/ocaml/issues/14655 (Issue Tracking)
github.com/ocaml/ocaml/pull/14674 (Issue Tracking)

Frequently asked questions

What is CVE-2026-34353?: CVE-2026-34353 is a medium-severity vulnerability in Ocaml, classified under Integer Overflow or Wraparound. CVSS score: 5.9/10. Published 2026-03-27.
How severe is CVE-2026-34353?: Medium severity. CVSS v3 base score is 5.9 out of 10.