Bug 1647246 (CVE-2018-16853)

Summary:	CVE-2018-16853 samba: S4U2Self crash with MIT KDC build
Product:	[Other] Security Response	Reporter:	Sam Fowler <sfowler>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED NOTABUG	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	abhgupta, abokovoy, anoopcs, asn, bmcclain, dbaker, dblechte, dfediuck, eedri, gdeschner, jarrpa, jokerman, jstephen, lmohanty, madam, mgoldboi, michal.skrivanek, rhs-smb, sankarshan, sbonazzo, sbose, security-response-team, sherold, sisharma, smohan, ssaha, ssorce, sthangav, trankin, vbellur
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	samba 4.7.12, samba 4.8.7, samba 4.9.3	Doc Type:	If docs needed, set a value
Doc Text:	Samba versions 4.7 and later, built with MIT Kerberos support, are vulnerable to a crash via the S4U2self extension. A user in a Samba Active Directory domain can crash the KDC when Samba is built in the non-default MIT Kerberos configuration.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2018-11-28 07:36:08 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:
Bug Depends On:	1654093
Bug Blocks:	1647248

Description Sam Fowler 2018-11-07 00:10:03 UTC

Samba versions 4.7 and later built with MIT Kerberos support are vulnerable to a crash via the S4U2self extension.


Upstream Bug:

https://bugzilla.samba.org/show_bug.cgi?id=13571

Comment 2 Sam Fowler 2018-11-28 03:01:47 UTC

External Reference:

https://www.samba.org/samba/security/CVE-2018-16853.html

Comment 3 Sam Fowler 2018-11-28 03:02:10 UTC

Acknowledgments:

Name: The Samba Team
Upstream: Isaac Boukris

Comment 4 Sam Fowler 2018-11-28 03:02:37 UTC

Created samba tracking bugs for this issue:

Affects: fedora-all [bug 1654093]

Comment 5 Huzaifa S. Sidhpurwala 2018-11-28 07:36:27 UTC

Statement:

This flaw does not affect the version of samba shipped with Red Hat Enterprise Linux because there is no support for samba as Active Directory Domain Controller.