USN-1520-1: Kerberos vulnerabilities

31 July 2012

krb5 vulnerabilities

A security issue affects these releases of Ubuntu and its derivatives:

  • Ubuntu 12.04 LTS
  • Ubuntu 11.10
  • Ubuntu 11.04
  • Ubuntu 10.04 LTS

Summary

Several security issues were fixed in Kerberos.

Software Description

  • krb5 - MIT Kerberos Network Authentication Protocol

Details

Emmanuel Bouillon discovered that the MIT krb5 Key Distribution Center (KDC) daemon could free an uninitialized pointer when handling a malformed AS-REQ message. A remote unauthenticated attacker could use this to cause a denial of service or possibly execute arbitrary code. (CVE-2012-1015)

Emmanuel Bouillon discovered that the MIT krb5 Key Distribution Center (KDC) daemon could dereference an uninitialized pointer while handling a malformed AS-REQ message. A remote unauthenticated attacker could use this to cause a denial of service or possibly execute arbitrary code. This issue only affected Ubuntu 12.04 LTS. (CVE-2012-1014)

Simo Sorce discovered that the MIT krb5 Key Distribution Center (KDC) daemon could dereference a NULL pointer when handling a malformed TGS-REQ message. A remote authenticated attacker could use this to cause a denial of service. (CVE-2012-1013)

It was discovered that the kadmin protocol implementation in MIT krb5 did not properly restrict access to the SET_STRING and GET_STRINGS operations. A remote authenticated attacker could use this to expose or modify sensitive information. This issue only affected Ubuntu 12.04 LTS. (CVE-2012-1012)

Update instructions

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

Ubuntu 12.04 LTS
krb5-admin-server - 1.10+dfsg~beta1-2ubuntu0.3
krb5-kdc - 1.10+dfsg~beta1-2ubuntu0.3
krb5-kdc-ldap - 1.10+dfsg~beta1-2ubuntu0.3
Ubuntu 11.10
krb5-admin-server - 1.9.1+dfsg-1ubuntu2.3
krb5-kdc - 1.9.1+dfsg-1ubuntu2.3
krb5-kdc-ldap - 1.9.1+dfsg-1ubuntu2.3
Ubuntu 11.04
krb5-admin-server - 1.8.3+dfsg-5ubuntu2.3
krb5-kdc - 1.8.3+dfsg-5ubuntu2.3
krb5-kdc-ldap - 1.8.3+dfsg-5ubuntu2.3
Ubuntu 10.04 LTS
krb5-admin-server - 1.8.1+dfsg-2ubuntu0.11
krb5-kdc - 1.8.1+dfsg-2ubuntu0.11
krb5-kdc-ldap - 1.8.1+dfsg-2ubuntu0.11

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

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

References