CVE-2023-31147

Insufficient randomness in generation of DNS query IDs in c-ares

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.

Category

5.9
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.09%
Third-Party Advisory github.com Third-Party Advisory fedoraproject.org Third-Party Advisory fedoraproject.org Third-Party Advisory gentoo.org
Affected: c-ares c-ares
Published at:
Updated at:

References

Link Tags
https://github.com/c-ares/c-ares/security/advisories/GHSA-8r8p-23f3-64c2 third party advisory
https://github.com/c-ares/c-ares/releases/tag/cares-1_19_1 release notes
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/B5Z5XFNXTNPTCBBVXFDNZQVLLIE6VRBY/ third party advisory mailing list
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UBFWILTA33LOSV23P44FGTQQIDRJHIY7/ third party advisory mailing list
https://security.gentoo.org/glsa/202310-09 third party advisory

Frequently Asked Questions

What is the severity of CVE-2023-31147?
CVE-2023-31147 has been scored as a medium severity vulnerability.
How to fix CVE-2023-31147?
To fix CVE-2023-31147, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-31147 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-31147 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-31147?
CVE-2023-31147 affects c-ares c-ares.
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