Veritas Backup Exec contains a privilege escalation vulnerability due to the use of an
OPENSSLDIR variable that specifies a location where an unprivileged Windows user can create files.
Veritas Backup Exec includes an OpenSSL component that specifies an
OPENSSLDIR variable as
/usr/local/ssl/. On the Windows platform, this path is interpreted as
C:\usr\local\ssl. Backup Exec contains a privileged service that uses this OpenSSL component. Because unprivileged Windows users can create subdirectories off of the system root, a user can create the appropriate path to a specially-crafted
openssl.cnf file to achieve arbitrary code execution with SYSTEM privileges.
By placing a specially-crafted
openssl.cnf in the
C:\usr\local\ssl directory, an unprivileged user may be able to execute arbitrary code with SYSTEM privileges on a Windows system with the vulnerable Veritas software installed.
Apply an update
Create a C:\usr\local\ssl directory
In cases where an update cannot be installed, this vulnerability can be mitigated by creating a
C:\usr\local\ssl directory and restricting ACLs to prevent unprivileged users from being able to write to this location.
This vulnerability was reported by Will Dormann of the CERT/CC.
This document was written by Will Dormann.