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Medium USN-7925-1 1 CVE

c-ares vulnerability

Published Dec 11, 2025 · Updated Apr 22, 2026

Ecosystem: Ubuntu

Summary

It was discovered that c-ares incorrectly handled terminating certain
queries after a maximum number of attempts. An attacker could possibly use
this issue to cause c-ares to crash, resulting in a denial of service.

Fixed packages 1

ReleasePackageFixed in
Ubuntu · 25.10 c-ares 1.34.5-1ubuntu0.1

Vulnerabilities 1

  • Medium 5.9
    CVE-2025-62408

    c-ares has a Use After Free vulnerability when connection is cleaned up after error

    c-ares is an asynchronous resolver library. Versions 1.32.3 through 1.34.5 terminate a query after maximum attempts when using read_answer() and process_answer(), which can cause a Denial of Service. This issue is fixed in version 1.34.6.

    c-ares c-ares fluent-bit c-ares Debian Ubuntu Azure Linux Alpine

References

  • report
    https://ubuntu.com/security/CVE-2025-62408