MIT Kerberos: Schwachstelle ermöglicht Denial of Service
WID-SEC-2023-2035 · first 11.08.2023 · updated 29.05.2026 · CVSS 7,5
What it is about
Kerberos ist ein verteilter Netzwerkdienst zur Authentifizierung. MIT Kerberos ist die freie Implementierung des "Kerberos network authentication protocol", des Massachusetts Institute of Technology (MIT). Ein entfernter, anonymer Angreifer kann eine Schwachstelle in MIT Kerberos ausnutzen, um einen Denial of Service Angriff durchzuführen.
Under what conditions?
Over the network and without logging in. This is the most dangerous combination: attackers can scan reachable devices automatically.
What can happen in the worst case
An attacker could use the vulnerability to
- einen Denial of Service Angriff durchzuführen
Am I affected?
Affected according to the BSI:
- Red Hat Enterprise Linux
- Gentoo Linux
- Xerox FreeFlow Print Server v9
- MIT Kerberos <krb5-1.21-3.fc38
- IBM Security Guardium 12.0
- RESF Rocky Linux
The installed version is usually shown under “Help → About” or in the device’s admin interface.
What helps?
Update to at least:
- MIT Kerberos krb5-1.21-3.fc38
Is the vulnerability already being exploited?
None of the CVEs is in the CISA catalogue of exploited vulnerabilities. That does not mean there are no attacks, only that none are documented.
Information and sources
- Original BSI advisory (WID)
- IBM Security Bulletin 7100884 vom 2023-12-20 www.ibm.com
- RedHat Bugzilla Bug ID: 2229113 vom 2023-08-10 bugzilla.redhat.com
- PoC vom 2023-08-10 github.com
- Red Hat Security Advisory RHSA-2023:6699 vom 2023-11-07 access.redhat.com
- Gentoo Linux Security Advisory GLSA-202405-11 vom 2024-05-05 security.gentoo.org
- XEROX Security Advisory XRX24-017 vom 2024-11-21 securitydocs.business.xerox.com
- Rocky Linux Security Advisory RLSA-2023:6699 vom 2026-05-28 errata.build.resf.org
CVE: CVE-2023-39975
Source: BSI warning and information service (CERT-Bund); CISA. The assessment of the conditions is my reading of the BSI text; the external pages are in their original language.