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.
Advisories
Source ID Title
Debian DLA Debian DLA DLA-3736-1 unbound security update
Debian DLA Debian DLA DLA-3816-1 bind9 security update
Debian DLA Debian DLA DLA-3859-1 systemd security update
Debian DLA Debian DLA DLA-3974-1 dnsmasq security update
Debian DSA Debian DSA DSA-5620-1 unbound security update
Debian DSA Debian DSA DSA-5621-1 bind9 security update
Debian DSA Debian DSA DSA-5626-1 pdns-recursor security update
Debian DSA Debian DSA DSA-5633-1 knot-resolver security update
Ubuntu USN Ubuntu USN USN-6633-1 Bind vulnerabilities
Ubuntu USN Ubuntu USN USN-6642-1 Bind vulnerabilities
Ubuntu USN Ubuntu USN USN-6657-1 Dnsmasq vulnerabilities
Ubuntu USN Ubuntu USN USN-6657-2 Dnsmasq vulnerabilities
Ubuntu USN Ubuntu USN USN-6665-1 Unbound vulnerabilities
Ubuntu USN Ubuntu USN USN-6723-1 Bind vulnerabilities
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

References
Link Providers
http://www.openwall.com/lists/oss-security/2024/02/16/2 cve-icon cve-icon
http://www.openwall.com/lists/oss-security/2024/02/16/3 cve-icon cve-icon
https://access.redhat.com/security/cve/CVE-2023-50868 cve-icon cve-icon
https://blog.powerdns.com/2024/02/13/powerdns-recursor-4-8-6-4-9-3-5-0-2-released cve-icon
https://bugzilla.suse.com/show_bug.cgi?id=1219826 cve-icon cve-icon
https://datatracker.ietf.org/doc/html/rfc5155 cve-icon cve-icon
https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-2024-01.html cve-icon cve-icon
https://gitlab.nic.cz/knot/knot-resolver/-/releases/v5.7.1 cve-icon cve-icon
https://kb.isc.org/docs/cve-2023-50868 cve-icon cve-icon cve-icon
https://lists.debian.org/debian-lts-announce/2024/02/msg00006.html cve-icon cve-icon
https://lists.debian.org/debian-lts-announce/2024/05/msg00011.html cve-icon cve-icon
https://lists.debian.org/debian-lts-announce/2024/09/msg00001.html cve-icon
https://lists.debian.org/debian-lts-announce/2024/11/msg00035.html cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6FV5O347JTX7P5OZA6NGO4MKTXRXMKOZ/ cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BUIP7T7Z4T3UHLXFWG6XIVDP4GYPD3AI/ cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HVRDSJVZKMCXKKPP6PNR62T7RWZ3YSDZ/ cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IGSLGKUAQTW5JPPZCMF5YPEYALLRUZZ6/ cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PNNHZSZPG2E7NBMBNYPGHCFI4V4XRWNQ/ cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RGS7JN6FZXUSTC2XKQHH27574XOULYYJ/ cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SVYA42BLXUCIDLD35YIJPJSHDIADNYMP/ cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TEXGOYGW7DBS3N2QSSQONZ4ENIRQEAPG/ cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UQESRWMJCF4JEYJEAKLRM6CT55GLJAB7/ cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZDZFMEKQTZ4L7RY46FCENWFB5MDT263R/ cve-icon cve-icon
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/BUIP7T7Z4T3UHLXFWG6XIVDP4GYPD3AI/ cve-icon
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/HVRDSJVZKMCXKKPP6PNR62T7RWZ3YSDZ/ cve-icon
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZDZFMEKQTZ4L7RY46FCENWFB5MDT263R/ cve-icon
https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2024q1/017430.html cve-icon cve-icon
https://nlnetlabs.nl/news/2024/Feb/13/unbound-1.19.1-released/ cve-icon cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2023-50868 cve-icon
https://security.netapp.com/advisory/ntap-20240307-0008/ cve-icon cve-icon
https://www.cve.org/CVERecord?id=CVE-2023-50868 cve-icon
https://www.isc.org/blogs/2024-bind-security-release/ cve-icon cve-icon
https://www.knot-resolver.cz/2024-02-13-knot-resolver-5.7.1.html cve-icon
History

Tue, 23 Dec 2025 20:30:00 +0000

Type Values Removed Values Added
First Time appeared Debian
Debian debian Linux
Fedoraproject
Fedoraproject fedora
Isc
Isc bind
Netapp
Netapp active Iq Unified Manager
Netapp bootstrap Os
Netapp h300s
Netapp h410c
Netapp h410s
Netapp h500s
Netapp h700s
Netapp hci Baseboard Management Controller
Netapp hci Compute Node
Powerdns
Powerdns recursor
CPEs cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:*
cpe:2.3:a:isc:bind:*:*:*:*:supported_preview:*:*:*
cpe:2.3:a:isc:bind:*:s1:*:*:supported_preview:*:*:*
cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:vmware_vsphere:*:*
cpe:2.3:a:netapp:hci_baseboard_management_controller:-:*:*:*:*:*:*:*
cpe:2.3:a:powerdns:recursor:*:*:*:*:*:*:*:*
cpe:2.3:h:netapp:h300s:-:*:*:*:*:*:*:*
cpe:2.3:h:netapp:h410c:-:*:*:*:*:*:*:*
cpe:2.3:h:netapp:h410s:-:*:*:*:*:*:*:*
cpe:2.3:h:netapp:h500s:-:*:*:*:*:*:*:*
cpe:2.3:h:netapp:h700s:-:*:*:*:*:*:*:*
cpe:2.3:h:netapp:hci_compute_node:-:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:39:*:*:*:*:*:*:*
cpe:2.3:o:netapp:bootstrap_os:-:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.2:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:8.4:*:*:*:*:*:*:*
Vendors & Products Debian
Debian debian Linux
Fedoraproject
Fedoraproject fedora
Isc
Isc bind
Netapp
Netapp active Iq Unified Manager
Netapp bootstrap Os
Netapp h300s
Netapp h410c
Netapp h410s
Netapp h500s
Netapp h700s
Netapp hci Baseboard Management Controller
Netapp hci Compute Node
Powerdns
Powerdns recursor

Tue, 04 Nov 2025 19:30:00 +0000


Tue, 04 Nov 2025 17:30:00 +0000

Type Values Removed Values Added
References

Mon, 03 Nov 2025 22:30:00 +0000

Type Values Removed Values Added
References

Wed, 16 Jul 2025 13:45:00 +0000

Type Values Removed Values Added
Metrics epss

{'score': 0.48504}

epss

{'score': 0.62382}


Mon, 12 May 2025 15:15:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N'}


Thu, 13 Feb 2025 01:00:00 +0000

Type Values Removed Values Added
CPEs cpe:/o:redhat:rhel_els:6

Fri, 13 Dec 2024 02:45:00 +0000

Type Values Removed Values Added
First Time appeared Redhat rhel Els
CPEs cpe:/o:redhat:rhel_els:7
Vendors & Products Redhat rhel Els

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published:

Updated: 2025-11-04T18:20:42.287Z

Reserved: 2023-12-14T00:00:00.000Z

Link: CVE-2023-50868

cve-icon Vulnrichment

Updated: 2025-11-04T18:20:42.287Z

cve-icon NVD

Status : Analyzed

Published: 2024-02-14T16:15:45.377

Modified: 2025-12-23T20:20:08.930

Link: CVE-2023-50868

cve-icon Redhat

Severity : Important

Publid Date: 2024-02-13T00:00:00Z

Links: CVE-2023-50868 - Bugzilla

cve-icon OpenCVE Enrichment

No data.

Weaknesses