USN-8844-1: c-ares vulnerability
Publication date
29 September 2026
Overview
c-ares could be made to crash or run programs if it received specially crafted network traffic.
Releases
Packages
- c-ares - library for asynchronous name resolution
Details
It was discovered that c-ares incorrectly handled certain query completion
callbacks. An attacker could possibly use this issue to trigger a use-
after-free or double-free, resulting in a denial of service or arbitrary
code execution.
It was discovered that c-ares incorrectly handled certain query completion
callbacks. An attacker could possibly use this issue to trigger a use-
after-free or double-free, resulting in a denial of service or arbitrary
code execution.
Update instructions
In general, a standard system update will make all the necessary changes.
Learn more about how to get the fixes.The problem can be corrected by updating your system to the following package versions:
| Ubuntu Release | Package Version | ||
|---|---|---|---|
| 26.04 LTS resolute | libcares2 – 1.34.6-1ubuntu0.1 | ||
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