CVE-2026-90698 memcached mcmc Tokenizer proto_text.c try_read_command_asciiauth out-of-bounds
Remote attackers can trigger an out-of-bounds read in memcached's ASCII auth tokenizer, potentially causing crashes or leaking memory.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-90698?
CVE-2026-90698 is a medium-severity memory corruption vulnerability in memcached, published on 14 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A security flaw has been discovered in memcached 1.6.41/1.6.42/1.6.43. This vulnerability affects the function try_read_command_asciiauth of the file proto_text.c of the component mcmc Tokenizer. The manipulation results in out-of-bounds read. It is possible to launch the attack remotely. The exploit has been released to the public and may be used for attacks. Upgrading to version 1.6.44 is able to resolve this issue. The patch is identified as af05c9302bba508b736c3da1d5670f63fe8b7db4. You should upgrade the affected component.
Which versions are affected by CVE-2026-90698?
How do I fix CVE-2026-90698?
Upgrade to a fixed version.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-90698 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-90698 exists.
Sources
Also known as DEBIAN-CVE-2026-90698, GHSA-xf89-37qr-gchh, OESA-2026-4101, UBUNTU-CVE-2026-90698, USN-8792-1.