CVE-2023-50868

7.5 HIGH
Published: February 14, 2024 Modified: December 23, 2025
View on NVD

Description

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
http://www.openwall.com/lists/oss-security/2024/02/16/2
Source: cve@mitre.org
Issue Tracking Mailing List
http://www.openwall.com/lists/oss-security/2024/02/16/3
Source: cve@mitre.org
Issue Tracking Mailing List
https://access.redhat.com/security/cve/CVE-2023-50868
Source: cve@mitre.org
Vendor Advisory
https://bugzilla.suse.com/show_bug.cgi?id=1219826
Source: cve@mitre.org
Issue Tracking
https://datatracker.ietf.org/doc/html/rfc5155
Source: cve@mitre.org
Technical Description
https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-2024-01.html
Source: cve@mitre.org
Vendor Advisory
https://gitlab.nic.cz/knot/knot-resolver/-/releases/v5.7.1
Source: cve@mitre.org
Release Notes
https://kb.isc.org/docs/cve-2023-50868
Source: cve@mitre.org
Third Party Advisory
https://lists.debian.org/debian-lts-announce/2024/02/msg00006.html
Source: cve@mitre.org
Vendor Advisory Mailing List
https://lists.debian.org/debian-lts-announce/2024/05/msg00011.html
Source: cve@mitre.org
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6FV5O347JTX7P5OZA6NGO4MKTXRXMKOZ/
Source: cve@mitre.org
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BUIP7T7Z4T3UHLXFWG6XIVDP4GYPD3AI/
Source: cve@mitre.org
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HVRDSJVZKMCXKKPP6PNR62T7RWZ3YSDZ/
Source: cve@mitre.org
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IGSLGKUAQTW5JPPZCMF5YPEYALLRUZZ6/
Source: cve@mitre.org
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PNNHZSZPG2E7NBMBNYPGHCFI4V4XRWNQ/
Source: cve@mitre.org
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RGS7JN6FZXUSTC2XKQHH27574XOULYYJ/
Source: cve@mitre.org
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SVYA42BLXUCIDLD35YIJPJSHDIADNYMP/
Source: cve@mitre.org
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TEXGOYGW7DBS3N2QSSQONZ4ENIRQEAPG/
Source: cve@mitre.org
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UQESRWMJCF4JEYJEAKLRM6CT55GLJAB7/
Source: cve@mitre.org
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZDZFMEKQTZ4L7RY46FCENWFB5MDT263R/
Source: cve@mitre.org
Vendor Advisory Mailing List
https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2024q1/017430.html
Source: cve@mitre.org
Mailing List Release Notes
https://nlnetlabs.nl/news/2024/Feb/13/unbound-1.19.1-released/
Source: cve@mitre.org
Release Notes
https://security.netapp.com/advisory/ntap-20240307-0008/
Source: cve@mitre.org
Vendor Advisory
https://www.isc.org/blogs/2024-bind-security-release/
Source: cve@mitre.org
Exploit Mitigation Press/Media Coverage
http://www.openwall.com/lists/oss-security/2024/02/16/2
Source: af854a3a-2127-422b-91ae-364da2661108
Issue Tracking Mailing List
http://www.openwall.com/lists/oss-security/2024/02/16/3
Source: af854a3a-2127-422b-91ae-364da2661108
Issue Tracking Mailing List
https://access.redhat.com/security/cve/CVE-2023-50868
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory
https://bugzilla.suse.com/show_bug.cgi?id=1219826
Source: af854a3a-2127-422b-91ae-364da2661108
Issue Tracking
https://datatracker.ietf.org/doc/html/rfc5155
Source: af854a3a-2127-422b-91ae-364da2661108
Technical Description
https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-2024-01.html
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory
https://gitlab.nic.cz/knot/knot-resolver/-/releases/v5.7.1
Source: af854a3a-2127-422b-91ae-364da2661108
Release Notes
https://kb.isc.org/docs/cve-2023-50868
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://lists.debian.org/debian-lts-announce/2024/02/msg00006.html
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.debian.org/debian-lts-announce/2024/05/msg00011.html
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.debian.org/debian-lts-announce/2024/09/msg00001.html
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.debian.org/debian-lts-announce/2024/11/msg00035.html
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6FV5O347JTX7P5OZA6NGO4MKTXRXMKOZ/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BUIP7T7Z4T3UHLXFWG6XIVDP4GYPD3AI/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HVRDSJVZKMCXKKPP6PNR62T7RWZ3YSDZ/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IGSLGKUAQTW5JPPZCMF5YPEYALLRUZZ6/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PNNHZSZPG2E7NBMBNYPGHCFI4V4XRWNQ/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RGS7JN6FZXUSTC2XKQHH27574XOULYYJ/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SVYA42BLXUCIDLD35YIJPJSHDIADNYMP/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TEXGOYGW7DBS3N2QSSQONZ4ENIRQEAPG/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UQESRWMJCF4JEYJEAKLRM6CT55GLJAB7/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZDZFMEKQTZ4L7RY46FCENWFB5MDT263R/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/BUIP7T7Z4T3UHLXFWG6XIVDP4GYPD3AI/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/HVRDSJVZKMCXKKPP6PNR62T7RWZ3YSDZ/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZDZFMEKQTZ4L7RY46FCENWFB5MDT263R/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory Mailing List
https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2024q1/017430.html
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Release Notes
https://nlnetlabs.nl/news/2024/Feb/13/unbound-1.19.1-released/
Source: af854a3a-2127-422b-91ae-364da2661108
Release Notes
https://security.netapp.com/advisory/ntap-20240307-0008/
Source: af854a3a-2127-422b-91ae-364da2661108
Vendor Advisory
https://www.isc.org/blogs/2024-bind-security-release/
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Mitigation Press/Media Coverage

53 reference(s) from NVD

Quick Stats

CVSS v3 Score
7.5 / 10.0
EPSS (Exploit Probability)
14.1%
94th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

CWE-400

Affected Vendors

debian netapp redhat powerdns isc fedoraproject

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