CVE-2026-75538 Integer overflow in OTP
An attacker can crash the Erlang VM via a signed integer overflow in the TCP driver, requiring specific packet mode configuration.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-75538?
CVE-2026-75538 is a high-severity vulnerability in Erlang OTP, published on 1 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
An attacker that connects to an open Erlang TCP port that uses the inet driver with {packet,4} mode can use a signed overflow in an incorrect packet length calculation to overflow the receive buffer into the VM allocator area and beyond up to about 2 GB.
This would easily trash the allocated block's allocator metadata footer, and the next block, if any, and most likely cause the BEAM VM to crash. Utilizing this with precision enough to achieve Remote Code Execution would be extremely unfeasible.
This issue affects OTP from OTP 17.0 before OTP 27.3.4.17, from OTP 28.0 before OTP 28.5.0.6, and from OTP 29.0 before OTP 29.0.6, corresponding to erts from 6.0 before 15.2.7.13, from 16.0 before 16.4.0.6, and from 17.0 before 17.0.6. Whether OTP before OTP 17.0, corresponding to erts before 6.0, is affected is unknown.
Which versions are affected by CVE-2026-75538?
How do I fix CVE-2026-75538?
Upgrade to a fixed version.
Is CVE-2026-75538 being exploited?
There is no known exploitation of CVE-2026-75538 in the wild and no public exploit code.
Sources
Also known as AZL-98499, DEBIAN-CVE-2026-75538, EEF-CVE-2026-75538, GHSA-8m6r-2pj2-25pm, UBUNTU-CVE-2026-75538.