Use After Free in C-ares

CVE-2025-62408

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.

Vulnerability class: Use-After-Free

EPSS: 0.004 (30.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

  • C-ares — versions > 1.32.3, < 1.34.6

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-62408?
CVE-2025-62408 is a medium-severity vulnerability in C-ares, classified under Use After Free. CVSS score: 5.9/10. Published 2025-12-08.
How severe is CVE-2025-62408?
Medium severity. CVSS v3 base score is 5.9 out of 10.