=========================================================================Ubuntu Security Notice USN-1233-1
October 18, 2011
krb5 vulnerabilities
=========================================================================
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 11.10
- Ubuntu 11.04
- Ubuntu 10.10
- Ubuntu 10.04 LTS
Summary:
Several denial of service issues were fixed in the Kerberos Key
Distribution Center (KDC).
Software Description:
- krb5: MIT Kerberos Network Authentication Protocol
Details:
Nalin Dahyabhai, Andrej Ota and Kyle Moffett discovered a NULL
pointer dereference in the KDC LDAP backend. An unauthenticated
remote attacker could use this to cause a denial of service. This
issue affected Ubuntu 11.10. (CVE-2011-1527)
Mark Deneen discovered that an assert() could be triggered in the
krb5_ldap_lockout_audit() function in the KDC LDAP backend and
the krb5_db2_lockout_audit() function in the KDC DB2 backend. An
unauthenticated remote attacker could use this to cause a denial of
service. (CVE-2011-1528)
It was discovered that a NULL pointer dereference could occur in the
lookup_lockout_policy() function in the KDC LDAP and DB2 backends.
An unauthenticated remote attacker could use this to cause a denial of
service. (CVE-2011-1529)
Update instructions:
The problem can be corrected by updating your system to the following
package versions:
Ubuntu 11.10:
krb5-kdc 1.9.1+dfsg-1ubuntu1.1
krb5-kdc-ldap 1.9.1+dfsg-1ubuntu1.1
Ubuntu 11.04:
krb5-kdc 1.8.3+dfsg-5ubuntu2.2
krb5-kdc-ldap 1.8.3+dfsg-5ubuntu2.2
Ubuntu 10.10:
krb5-kdc 1.8.1+dfsg-5ubuntu0.8
krb5-kdc-ldap 1.8.1+dfsg-5ubuntu0.8
Ubuntu 10.04 LTS:
krb5-kdc 1.8.1+dfsg-2ubuntu0.10
krb5-kdc-ldap 1.8.1+dfsg-2ubuntu0.10
In general, a standard system update will make all the necessary changes.
References:
https://ubuntu.com/security/notices/USN-1233-1
CVE-2011-1527, CVE-2011-1528, CVE-2011-1529
Package Information:
https://launchpad.net/ubuntu/+source/krb5/1.9.1+dfsg-1ubuntu1.1
https://launchpad.net/ubuntu/+source/krb5/1.8.3+dfsg-5ubuntu2.2
https://launchpad.net/ubuntu/+source/krb5/1.8.1+dfsg-5ubuntu0.8
https://launchpad.net/ubuntu/+source/krb5/1.8.1+dfsg-2ubuntu0.10