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.
Exploits (1)
nomisec
WORKING POC
6 stars
by Goethe-Universitat-Cybersecurity · poc
https://github.com/Goethe-Universitat-Cybersecurity/NSEC3-Encloser-Attack
References (29)
Core 29
Core References
Technical Description
https://datatracker.ietf.org/doc/html/rfc5155
Vendor Advisory
https://access.redhat.com/security/cve/CVE-2023-50868
Issue Tracking
https://bugzilla.suse.com/show_bug.cgi?id=1219826
Vendor Advisory
https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-2024-01.html
Third Party Advisory
https://kb.isc.org/docs/cve-2023-50868
Mailing List, Release Notes
https://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2024q1/017430.html
Vendor Advisory
https://security.netapp.com/advisory/ntap-20240307-0008/
Exploit, Mitigation, Press/Media Coverage
https://www.isc.org/blogs/2024-bind-security-release/
Vendor Advisory, Mailing List
https://lists.debian.org/debian-lts-announce/2024/09/msg00001.html
Vendor Advisory, Mailing List
https://lists.debian.org/debian-lts-announce/2024/11/msg00035.html
Vendor Advisory, Mailing List
https://lists.fedoraproject.org/archives/list/[email protected]/message/BUIP7T7Z4T3UHLXFWG6XIVDP4GYPD3AI/
Vendor Advisory, Mailing List
https://lists.fedoraproject.org/archives/list/[email protected]/message/HVRDSJVZKMCXKKPP6PNR62T7RWZ3YSDZ/
Vendor Advisory, Mailing List
https://lists.fedoraproject.org/archives/list/[email protected]/message/ZDZFMEKQTZ4L7RY46FCENWFB5MDT263R/
Issue Tracking, Mailing List mailing-list
http://www.openwall.com/lists/oss-security/2024/02/16/2
Issue Tracking, Mailing List mailing-list
http://www.openwall.com/lists/oss-security/2024/02/16/3
Vendor Advisory, Mailing List vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SVYA42BLXUCIDLD35YIJPJSHDIADNYMP/
Vendor Advisory, Mailing List vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BUIP7T7Z4T3UHLXFWG6XIVDP4GYPD3AI/
Vendor Advisory, Mailing List vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PNNHZSZPG2E7NBMBNYPGHCFI4V4XRWNQ/
Vendor Advisory, Mailing List mailing-list
https://lists.debian.org/debian-lts-announce/2024/02/msg00006.html
Vendor Advisory, Mailing List vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TEXGOYGW7DBS3N2QSSQONZ4ENIRQEAPG/
Vendor Advisory, Mailing List vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UQESRWMJCF4JEYJEAKLRM6CT55GLJAB7/
Vendor Advisory, Mailing List vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RGS7JN6FZXUSTC2XKQHH27574XOULYYJ/
Vendor Advisory, Mailing List vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HVRDSJVZKMCXKKPP6PNR62T7RWZ3YSDZ/
Vendor Advisory, Mailing List vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6FV5O347JTX7P5OZA6NGO4MKTXRXMKOZ/
Vendor Advisory, Mailing List vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IGSLGKUAQTW5JPPZCMF5YPEYALLRUZZ6/
Vendor Advisory, Mailing List vendor-advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZDZFMEKQTZ4L7RY46FCENWFB5MDT263R/
Vendor Advisory, Mailing List mailing-list
https://lists.debian.org/debian-lts-announce/2024/05/msg00011.html
Scores
CVSS v3
7.5
EPSS
0.1180
EPSS Percentile
93.8%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-400
Status
published
Products (16)
debian/debian_linux
10.0
debian/debian_linux
11.0
fedoraproject/fedora
38
fedoraproject/fedora
39
isc/bind
9.0.0 - 9.16.48
isc/bind
9.18.11 - 9.18.24
isc/bind
9.9.3 - 9.16.48
netapp/active_iq_unified_manager
netapp/bootstrap_os
netapp/hci_baseboard_management_controller
... and 6 more
Published
Feb 14, 2024
Tracked Since
Feb 18, 2026