CVE-2018-1050: Samba - Security Announcement Archive

CVE-2018-1050.html:

==================================================================== == Subject: Denial of Service Attack on external print server. == == CVE ID#: CVE-2018-1050 == == Versions: All versions of Samba from 3.6.0 onwards. == == Summary: Missing null pointer checks may crash the external == print server process. == ====================================================================

=========== Description ===========

All versions of Samba from 3.6.0 onwards are vulnerable to a denial of service attack when the RPC spoolss service is configured to be run as an external daemon. Missing input sanitization checks on some of the input parameters to spoolss RPC calls could cause the print spooler service to crash.

There is no known vulnerability associated with this error, merely a denial of service. If the RPC spoolss service is left by default as an internal service, all a client can do is crash its own authenticated connection.

================== Patch Availability ==================

A patch addressing this defect has been posted to

http://www.samba.org/samba/security/

Additionally, Samba 4.7.6, 4.6.14 and 4.5.16 have been issued as security releases to correct the defect. Patches against older Samba versions are available at http://samba.org/samba/patches/. Samba vendors and administrators running affected versions are advised to upgrade or apply the patch as soon as possible.

========== Workaround ==========

Ensure the parameter:

rpc_server:spoolss = external

is not set in the [global] section of your smb.conf.

======= Credits =======

This problem was found by the Synopsys Defensics intelligent fuzz testing tool. Jeremy Allison of Google and the Samba Team provided the fix.