Ubuntu 24.10: USN-7257-1 critical: Kerberos authentication bypass

ubuntu

February 5, 2025

A system authentication measure could be bypassed.

Summary

A system authentication measure could be bypassed.

Software Description:

- krb5: MIT Kerberos Network Authentication Protocol

Details:

Goldberg, Miro Haller, Nadia Heninger, Mike Milano, Dan Shumow, Marc

Stevens, and Adam Suhl discovered that Kerberos incorrectly authenticated

certain responses. An attacker able to intercept communications between a

RADIUS client and server could possibly use this issue to forge responses,

bypass authentication, and access network devices and services.

This update introduces support for the Message-Authenticator attribute in

non-EAP authentication methods for communications between Kerberos and a

RADIUS server.

Topics Covered

security advisory threat Ubuntu authentication krb5 bypass

Update Instructions

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 24.10
   libk5crypto3                    1.21.3-3ubuntu0.1
   libkrad0                        1.21.3-3ubuntu0.1

Ubuntu 24.04 LTS
   libk5crypto3                    1.20.1-6ubuntu2.3
   libkrad0                        1.20.1-6ubuntu2.3

Ubuntu 22.04 LTS
   libk5crypto3                    1.19.2-2ubuntu0.5
   libkrad0                        1.19.2-2ubuntu0.5

Ubuntu 20.04 LTS
   libk5crypto3                    1.17-6ubuntu4.8
   libkrad0                        1.17-6ubuntu4.8

Ubuntu 18.04 LTS
   libk5crypto3                    1.16-2ubuntu0.4+esm3
                                   Available with Ubuntu Pro
   libkrad0                        1.16-2ubuntu0.4+esm3
                                   Available with Ubuntu Pro

Ubuntu 16.04 LTS
   libk5crypto3                    1.13.2+dfsg-5ubuntu2.2+esm6
                                   Available with Ubuntu Pro
   libkrad0                        1.13.2+dfsg-5ubuntu2.2+esm6
                                   Available with Ubuntu Pro

Ubuntu 14.04 LTS
   libk5crypto3                    1.12+dfsg-2ubuntu5.4+esm6
                                   Available with Ubuntu Pro
   libkrad0                        1.12+dfsg-2ubuntu5.4+esm6
                                   Available with Ubuntu Pro

In general, a standard system update will make all the necessary changes.