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.
Published: 2023-05-25
Score: 5.9 Medium
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

No vendor fix or workaround currently provided.

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Tracking

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Advisories
Source ID Title
EUVD EUVD EUVD-2023-35463 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.
History

Wed, 16 Jul 2025 13:45:00 +0000

Type Values Removed Values Added
Metrics epss

{'score': 0.00087}

epss

{'score': 0.00089}


Thu, 16 Jan 2025 19:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Subscriptions

C-ares Project C-ares
Fedoraproject Fedora
Redhat Enterprise Linux Rhel Eus Rhel Software Collections
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2025-02-13T16:49:46.904Z

Reserved: 2023-04-24T21:44:10.418Z

Link: CVE-2023-31147

cve-icon Vulnrichment

Updated: 2024-08-02T14:45:25.630Z

cve-icon NVD

Status : Modified

Published: 2023-05-25T22:15:09.833

Modified: 2024-11-21T08:01:29.420

Link: CVE-2023-31147

cve-icon Redhat

Severity : Moderate

Publid Date: 2023-05-22T00:00:00Z

Links: CVE-2023-31147 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses