CVE-2016-3120

Published: 01 August 2016

The validate_as_request function in kdc_util.c in the Key Distribution Center (KDC) in MIT Kerberos 5 (aka krb5) before 1.13.6 and 1.4.x before 1.14.3, when restrict_anonymous_to_tgt is enabled, uses an incorrect client data structure, which allows remote authenticated users to cause a denial of service (NULL pointer dereference and daemon crash) via an S4U2Self request.

From the Ubuntu security team

It was discovered that Kerberos incorrectly handled certain data structures. A remote authenticated attacker could possibly use this issue to cause a denial of service.

Priority

Medium

CVSS 3 base score: 6.5

Status

Package Release Status
krb5
Launchpad, Ubuntu, Debian
Upstream
Released (1.14.3+dfsg-1)
Ubuntu 20.10 (Groovy Gorilla) Not vulnerable
(1.14.3+dfsg-2ubuntu1)
Ubuntu 20.04 LTS (Focal Fossa) Not vulnerable
(1.14.3+dfsg-2ubuntu1)
Ubuntu 18.04 LTS (Bionic Beaver) Not vulnerable
(1.14.3+dfsg-2ubuntu1)
Ubuntu 16.04 LTS (Xenial Xerus)
Released (1.13.2+dfsg-5ubuntu2.1)
Ubuntu 14.04 ESM (Trusty Tahr)
Released (1.12+dfsg-2ubuntu5.4)
Ubuntu 12.04 ESM (Precise Pangolin) Needed

Patches:
Upstream: https://github.com/krb5/krb5/commit/93b4a6306a0026cf1cc31ac4bd8a49ba5d034ba7
Binaries built from this source package are in Universe and so are supported by the community.