CVE-2026-18743 Popt-devel: popt-static: short realloc in poptconfigfiletostring
An attacker can cause denial of service in applications using popt by providing crafted configuration content that triggers heap metadata corruption.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-18743?
CVE-2026-18743 is a low-severity memory corruption vulnerability in Red Hat Enterprise Linux 10, published on 1 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
A flaw was found in popt. This vulnerability allows an attacker to provide specially crafted configuration content to a host, which, when loaded, can lead to a small memory corruption issue. This occurs because of an error in how the `poptConfigFileToString` function reallocates memory for buffers. Successful exploitation could result in heap metadata corruption, potentially causing the affected process to become unavailable (denial of service).
Weakness: CWE-131
Which versions are affected by CVE-2026-18743?
How do I fix CVE-2026-18743?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-18743 being exploited?
There is no known exploitation of CVE-2026-18743 in the wild and no public exploit code.
Sources
Also known as AZL-98234, AZL-98565, BELL-CVE-2026-18743, DEBIAN-CVE-2026-18743, ECHO-0994-b63c-bb57, GHSA-2r56-6h49-5c5r and 5 more.