MIT krb5 can perform an incorrect length check inside an ASN.1
decoder. This only presents a problem in the PK-INIT code paths. In
the MIT krb5 KDC or kinit program, this could lead to spurious
malloc() failures or, under some conditions, program crash. We have
heard reports of the spurious malloc() failures, but nobody has yet
made the publicly made the connection to a security issue.
This issue only affects krb5 1.6.3+. Prior releases contained the vulnerable code, but the vulnerability is masked due to operations perfomed by other code. so this does not affect Red Hat Enterprise Linux 2.1, 3, 4, or 5.
Public now via:
krb5-1.6.3-16.fc9 has been pushed to the Fedora 9 stable repository. If problems still persist, please make note of it in this bug report.
krb5-1.6.3-18.fc10 has been pushed to the Fedora 10 stable repository. If problems still persist, please make note of it in this bug report.
Even though this problem was not exposed in the krb5 versions shipped in Red Hat Enterprise Linux 2.1, 3, 4, and 5 and hence did not create a security flaw on those versions, upstream patch addressing underlying problem being part of the MITKRB5-SA-2009-001 patch was included in the updates addressing other ASN.1 decoding issue - CVE-2009-0846 and was released in following errata:
This issue was addressed in: