USN-1030-1: Kerberos vulnerabilities

Releases

• Ubuntu 10.10
• Ubuntu 10.04
• Ubuntu 9.10
• Ubuntu 8.04
• Ubuntu 6.06

Packages

• krb5 -

Details

It was discovered that Kerberos did not properly determine the
acceptability of certain checksums. A remote attacker could use certain
checksums to alter the prompt message, modify a response to a Key
Distribution Center (KDC) or forge a KRB-SAFE message. (CVE-2010-1323)

It was discovered that Kerberos did not properly determine the
acceptability of certain checksums. A remote attacker could use certain
checksums to forge GSS tokens or gain privileges. This issue only affected
Ubuntu 9.10, 10.04 LTS and 10.10. (CVE-2010-1324)

It was discovered that Kerberos did not reject RC4 key-derivation
checksums. An authenticated remote user could use this issue to forge
AD-SIGNEDPATH or AD-KDC-ISSUED signatures and possibly gain privileges.
This issue only affected Ubuntu 10.04 LTS and 10.10. (CVE-2010-4020)

It was discovered that Kerberos did not properly restrict the use of TGT
credentials for armoring TGS requests. A remote authenticated user could
use this flaw to impersonate a client. This issue only affected Ubuntu
9.10. (CVE-2010-4021)

Update instructions

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

Ubuntu 9.10

• libkrb5-3 - 1.7dfsg~beta3-1ubuntu0.7

Ubuntu 8.04

• libkrb53 - 1.6.dfsg.3~beta1-2ubuntu1.6

Ubuntu 6.06

• libkrb53 - 1.4.3-5ubuntu0.12

Ubuntu 10.10

• libkrb5-3 - 1.8.1+dfsg-5ubuntu0.2

Ubuntu 10.04

• libkrb5-3 - 1.8.1+dfsg-2ubuntu0.4

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

References

• CVE-2010-1323
• CVE-2010-1324
• CVE-2010-4021
• CVE-2010-4020