Local denial of service in c-ares

1) Out-of-bounds read

EUVDB-ID: #VU86807

Risk: Low

CVSSv3.1: 3.9 [CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2024-25629

CWE-ID: CWE-125 - Out-of-bounds read

Exploit availability: No

Description

The vulnerability allows a local user to perform a denial of service (DoS) attack.

The vulnerability exists due to a boundary error within the ares__read_line() function when parsing local configuration files, such as `/etc/resolv.conf`, `/etc/nsswitch.conf`, or `HOSTALIASES` file. A local user can insert a NULL character as the first character in a new line into one of the configuration files and crash the application.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

c-ares: 1.0.0 - 1.70.0

External links

http://github.com/c-ares/c-ares/security/advisories/GHSA-mg26-v6qh-x48q
http://github.com/c-ares/c-ares/commit/a804c04ddc8245fc8adf0e92368709639125e183

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.