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CVE-2023-50868

The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC 9276 guidance is skipped) allows remote attackers to cause a den

Published
Last modified
published
Not listed in CISA KEV
1 proof of concept on GitHub
  • Exploitation: none
  • Automatable: yes
  • Technical impact: partial

Summary

The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC 9276 guidance is skipped) allows remote attackers to cause a denial of service (CPU consumption for SHA-1 computations) via DNSSEC responses in a random subdomain attack, aka the "NSEC3" issue. The RFC 5155 specification implies that an algorithm must perform thousands of iterations of a hash function in certain situations.

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: none · Automatable: yes · Technical impact: partial

  3. Record last updated
  4. EPSS reached 10%

    FIRST estimates at least a 10% chance of exploitation in the next 30 days

Affected versions

  • n/a n/a

    Version range not reported

References 25

nlnetlabs.nl

docs.powerdns.com

isc.org

datatracker.ietf.org

kb.isc.org

gitlab.nic.cz

lists.thekelleys.org.uk

access.redhat.com

bugzilla.suse.com

openwall.com

lists.fedoraproject.org

lists.debian.org

security.netapp.com

GitHub · Goethe-Universitat-Cybersecurity/NSEC3-Encloser-Attack