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Medium ALAS2-2024-2646 1 CVE

Moderate: c-ares security update (Amazon Linux 2)

Published Sep 25, 2024 · Updated Oct 2, 2024

Summary

Package updates are available for Amazon Linux 2 that fix the following vulnerabilities: CVE-2023-31147: Insufficient randomness in generation of DNS query IDs 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.

Fixed packages 3

ReleasePackageFixed in
Amazon Linux · 2 c-ares 0:1.19.1-1.amzn2.0.1
Amazon Linux · 2 c-ares-debuginfo 0:1.19.1-1.amzn2.0.1
Amazon Linux · 2 c-ares-devel 0:1.19.1-1.amzn2.0.1

Vulnerabilities 1

  • Medium 5.9

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

    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 outp…

References

  • web
    https://alas.aws.amazon.com/cve/html/CVE-2023-31147.html