Security vulnerability in Heimdal Kerberos protocol (CVE-2017-11103)

  • 7021155
  • 01-Aug-2017
  • 12-Dec-2017

Environment

Micro Focus Filr 3.2

Situation

Upstream Information CVE-2017-11103 at MITRE

Heimdal before 7.4 allows remote attackers to impersonate services with Orpheus' Lyre attacks because it obtains service-principal names in a way that violates the Kerberos 5 protocol specification. In _krb5_extract_ticket() the KDC-REP service name must be obtained from the encrypted version stored in 'enc_part' instead of the unencrypted version stored in 'ticket'. Use of the unencrypted version provides an opportunity for successful server impersonation and other attacks. NOTE: this CVE is only for Heimdal and other products that embed Heimdal code; it does not apply to other instances in which this part of the Kerberos 5 protocol specification is violated.

Resolution

A fix for this issue is available in the Filr 3.3 Security Update 3.