Use-after-free in c-ares - CVE-2025-62408
Published: December 8, 2025
Vulnerability identifier: #VU119383
CSH Severity: Medium
CVSS v4: 6 [CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2025-62408
CWE-ID: CWE-416
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to perform a denial of service attack.
The vulnerability exists due to a use-after-free error within the read_answer() function when process_answer() terminates a query such as after maximum attempts. A remote attacker can perform a denial of service attack.
Note, the vulnerability exists due to an incomplete fix for #VU107155 (CVE-2025-31498).
Affected software
c-ares
Debian Linux
Ubuntu
watsonx.data
Nessus Network Monitor
c-ares (Ubuntu package)
c-ares (Debian package)
Debian Linux
Ubuntu
watsonx.data
Nessus Network Monitor
c-ares (Ubuntu package)
c-ares (Debian package)
How to mitigate CVE-2025-62408
Install updates from vendor's website.
c-ares - update to 1.34.6
watsonx.data - update to 2.3.1
Nessus Network Monitor - update to 6.5.3
c-ares (Ubuntu package) - addressed in versions 1.34.4-2.1ubuntu0.2, 1.34.5-1ubuntu0.1
c-ares (Debian package) - update to 1.34.5-1+deb13u1
watsonx.data - update to 2.3.1
Nessus Network Monitor - update to 6.5.3
c-ares (Ubuntu package) - addressed in versions 1.34.4-2.1ubuntu0.2, 1.34.5-1ubuntu0.1
c-ares (Debian package) - update to 1.34.5-1+deb13u1