Bug 1024547 (CVE-2013-4476)

Summary: CVE-2013-4476 samba: world-readable key.pem with Samba 4 AD DC
Product: [Other] Security Response Reporter: Vincent Danen <vdanen>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED NOTABUG QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: aavati, abokovoy, asn, gdeschner, jkurik, jlayton, pfrields, rfortier, rhs-bugs, sbose, security-response-team, ssaha, ssorce, vbellur
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: samba 4.0.11, samba 4.1.1 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2013-10-29 22:08:01 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Vincent Danen 2013-10-29 22:05:39 UTC 
It was reported [1] that when Samba 4.x is used as an Active Directory Domain Controller (AD DC) that the /var/lib/samba/private/tls directory was world-readable.  This directory also contained the private openssl key (key.pem) used, and it also was world-readable.  This could allow a local user to obtain the private key of the Samba AD DC.

Note: this issue only affects Samba 4.x that is compiled as an Active Directory Domain Controller.  Current Fedora packages are not compiled in this way due to current Heimdal/MIT Kerberos incompatibilities [2].

[1] https://bugzilla.samba.org/show_bug.cgi?id=10234
[2] https://fedoraproject.org/wiki/Features/Samba4
Comment 1 Vincent Danen 2013-10-29 22:08:01 UTC 
Statement:

Not vulnerable. This issue did not affect the versions of samba or samba3x as shipped with Red Hat Enterprise Linux 5 and 6 as they did not include support for acting as an Active Directory Domain Controller.
Comment 3 Tomas Hoger 2013-11-11 18:59:31 UTC 
Public now via upstream advisory, fixed in upstream Samba versions 4.0.11 and 4.1.1.

External References:

http://www.samba.org/samba/security/CVE-2013-4476
Comment 4 Tomas Hoger 2013-11-11 19:09:09 UTC 
Upstream bug report (currently non-public):
https://bugzilla.samba.org/show_bug.cgi?id=10234

Upstream commits:
http://git.samba.org/?p=samba.git;a=commitdiff;h=8eae8d2
http://git.samba.org/?p=samba.git;a=commitdiff;h=63d98ed
http://git.samba.org/?p=samba.git;a=commitdiff;h=83a3ae1
http://git.samba.org/?p=samba.git;a=commitdiff;h=cf29fb2
http://git.samba.org/?p=samba.git;a=commitdiff;h=e0248cd
http://git.samba.org/?p=samba.git;a=commitdiff;h=22af043