Vulnerability identifier: #VU76424

Vulnerability risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-31124

CWE-ID: CWE-338

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
c-ares
Universal components / Libraries / Libraries used by multiple products

Vendor: c-ares.haxx.se

Description

The vulnerability allows a remote attacker to perform spoofing attack.

The vulnerability exists due to an error when cross-compiling c-ares and using the autotools build system. As a result, the CARES_RANDOM_FILE is not be set, which results in usage of a rand() function as a fallback, leading to weak entropy.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

c-ares: 1.0.0 - 1.19.0

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External links
http://seclists.org/oss-sec/2023/q2/188
http://github.com/c-ares/c-ares/releases/tag/cares-1_19_1

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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