CVE-2026-87734 Denial of service in utcp
Remote attackers can cause denial of service in applications using the utcp OCaml library via out-of-order segment reassembly.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-87734?
CVE-2026-87734 is a high-severity denial of service vulnerability in OCaml utcp, published on 9 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
An issue was discovered in the utcp package before 0.0.6 for OCaml. Out-of-order segment reassembly allows remote denial of service.
Weakness: CWE-923
Which versions are affected by CVE-2026-87734?
How do I fix CVE-2026-87734?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-87734 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-87734 exists.
Sources
Also known as GHSA-798p-53r8-rvx4, OSEC-2026-11.