CVE-2023-31147

MEDIUM

c-ares < 1.19.1 - Use of Insufficiently Random Values for DNS Query IDs

Title source: llm
STIX 2.1

Description

c-ares is an asynchronous resolver library. When /dev/urandom or RtlGenRandom() are unavailable, c-ares uses rand() to generate random numbers used for DNS query ids. This is not a CSPRNG, and it is also not seeded by srand() so will generate predictable output. Input from the random number generator is fed into a non-compilant RC4 implementation and may not be as strong as the original RC4 implementation. No attempt is made to look for modern OS-provided CSPRNGs like arc4random() that is widely available. This issue has been fixed in version 1.19.1.

References (5)

Core 5

Scores

CVSS v3 5.9
EPSS 0.0091
EPSS Percentile 55.0%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-330
Status published
Products (3)
c-ares_project/c-ares < 1.19.1
fedoraproject/fedora 37
fedoraproject/fedora 38
Published May 25, 2023
Tracked Since Feb 18, 2026