CVE-2023-50868
HIGH 7.5EPSS 73.7%
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.
- CVSS v3.1 NVD
- 7.5 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS v3.1 CNA
- 7.5 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - EPSS
- 73.72% chance of exploitation in the next 30 days, 99th percentile
- Published
- 2024-02-14
- Updated
- 2025-11-04
Proof-of-concept exploits (2)
- Goethe-Universitat-Cybersecurity/NSEC3-Encloser-Attack6★ · 2024-05-27
- nsec-submission/nsec3-submission0★ · 2024-03-13
Security advisories
- https://access.redhat.com/security/cve/CVE-2023-50868
- https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-2024-01.html
- https://lists.debian.org/debian-lts-announce/2024/02/msg00006.html
- https://lists.debian.org/debian-lts-announce/2024/05/msg00011.html
- https://lists.debian.org/debian-lts-announce/2024/09/msg00001.html
- https://lists.debian.org/debian-lts-announce/2024/11/msg00035.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/…
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/…
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/…
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/…
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/…
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/…
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/…
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/…
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/…
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/…
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/me…
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/me…
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/me…
- https://security.netapp.com/advisory/ntap-20240307-0008
- https://kb.isc.org/docs/cve-2023-50868
- https://www.isc.org/blogs/2024-bind-security-release
- https://gitlab.nic.cz/knot/knot-resolver/-/releases/v5.7.1
- https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2024q1/017430.html
- https://nlnetlabs.nl/news/2024/Feb/13/unbound-1.19.1-released
- http://www.openwall.com/lists/oss-security/2024/02/16/2
- http://www.openwall.com/lists/oss-security/2024/02/16/3
- https://bugzilla.suse.com/show_bug.cgi?id=1219826