Amazon Linux 1 Security Advisory: ALAS-2015-624
Advisory Release Date: 2015-12-14 10:00 Pacific
Advisory Updated Date: 2015-12-13 14:23 Pacific
A flaw was found in the OTP kdcpreauth module of MIT Kerberos. A remote attacker could use this flaw to bypass the requires_preauth flag on a client principal and obtain a ciphertext encrypted in the principal's long-term key. This ciphertext could be used to conduct an off-line dictionary attack against the user's password.
It was found that the krb5_read_message() function of MIT Kerberos did not correctly sanitize input, and could create invalid krb5_data objects. A remote, unauthenticated attacker could use this flaw to crash a Kerberos child process via a specially crafted request.
Affected Packages:
krb5
Issue Correction:
Run yum update krb5 to update your system.
i686:
krb5-server-1.13.2-10.39.amzn1.i686
krb5-libs-1.13.2-10.39.amzn1.i686
krb5-debuginfo-1.13.2-10.39.amzn1.i686
krb5-workstation-1.13.2-10.39.amzn1.i686
krb5-server-ldap-1.13.2-10.39.amzn1.i686
krb5-devel-1.13.2-10.39.amzn1.i686
krb5-pkinit-openssl-1.13.2-10.39.amzn1.i686
src:
krb5-1.13.2-10.39.amzn1.src
x86_64:
krb5-devel-1.13.2-10.39.amzn1.x86_64
krb5-pkinit-openssl-1.13.2-10.39.amzn1.x86_64
krb5-debuginfo-1.13.2-10.39.amzn1.x86_64
krb5-server-1.13.2-10.39.amzn1.x86_64
krb5-workstation-1.13.2-10.39.amzn1.x86_64
krb5-libs-1.13.2-10.39.amzn1.x86_64
krb5-server-ldap-1.13.2-10.39.amzn1.x86_64