CVE-2023-31147
Insufficient randomness in generation of DNS query IDs in c-ares
At a glance
- Severity
- MEDIUM 5.9
- EPSS
- EPSS 0.90 % · percentile 59 (2026-10-27)
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Modified
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.
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | MEDIUM 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N | GitHub_M |
| CVSS 3.1 | MEDIUM 5.9 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N | NVD · security-advisories@github.com (Secondary) |
| CVSS 3.1 | MEDIUM 6.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N | NVD · nvd@nist.gov (Primary) |
Weaknesses (CWE)
European references
- ENISA EUVD · EUVD-2023-35463
- GCVE · GCVE-0-2023-31147
CERT-FR advisories
- CERTFR-2025-AVI-0170 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0866 — Multiples vulnérabilités dans les produits Juniper Networks · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0156 — Multiples vulnérabilités dans les produits Tenable · cert.ssi.gouv.fr
- CERTFR-2024-AVI-0119 — Multiples vulnérabilités dans les produits Siemens · cert.ssi.gouv.fr
- CERTFR-2023-AVI-0499 — Multiples vulnérabilités dans Tenable Nessus Network Monitor · cert.ssi.gouv.fr
Affected configurations (NVD CPE)
cpe:2.3:a:c-ares_project:c-ares:*:*:*:*:*:*:*:*< 1.19.1cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*
Affected products
| Product | Versions |
|---|---|
| c-ares · c-ares | affected < 1.19.1 |
References
- https://github.com/c-ares/c-ares/security/advisories/GHSA-8r8p-23f3-64c2
- https://github.com/c-ares/c-ares/releases/tag/cares-1_19_1
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/B5Z5XFNXTNPTCBBVXFDNZQVLLIE6VRBY/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UBFWILTA33LOSV23P44FGTQQIDRJHIY7/
- https://security.gentoo.org/glsa/202310-09
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| CERT-FR (ANSSI) | Licence Ouverte / Etalab 2.0 |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |