Bug 1418952 (CVE-2017-5885)

Summary:	CVE-2017-5885 gtk-vnc: Integer overflow when processing SetColorMapEntries
Product:	[Other] Security Response	Reporter:	Adam Mariš <amaris>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	berrange, bmcclain, cfergeau, dblechte, eedri, erik-fedora, fidencio, lsurette, mgoldboi, michal.skrivanek, rh-spice-bugs, rjones, sbonazzo, srevivo, virt-maint, ykaul
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:	An integer overflow flaw was found in gtk-vnc. A remote malicious VNC server could use this flaw to crash VNC viewers which are based on the gtk-vnc library.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2019-06-08 03:07:01 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:
Bug Depends On:	1418955, 1418956, 1425367
Bug Blocks:	1415638, 1418954

Description Adam Mariš 2017-02-03 09:03:39 UTC

It was found that vnc_connection_server_message() and vnc_color_map_set() functions do not check for integer overflow properly, leading to a malicious server being able to overwrite parts of the client memory, possibly leading to remote code execution under privileges of user running the VNC client.

Upstream bug:

https://bugzilla.gnome.org/show_bug.cgi?id=778050

Upstream patch:

https://git.gnome.org/browse/gtk-vnc/commit/?id=c8583fd3783c5b811590

Comment 1 Adam Mariš 2017-02-03 09:13:14 UTC

Created gtk-vnc tracking bugs for this issue:

Affects: fedora-all [bug 1418955]

Comment 2 Adam Mariš 2017-02-03 09:13:29 UTC

Created mingw-gtk-vnc tracking bugs for this issue:

Affects: fedora-all [bug 1418956]

Comment 3 Adam Mariš 2017-02-06 08:45:22 UTC

CVE assignment:

http://openwall.com/lists/oss-security/2017/02/05/5

Comment 4 Daniel Berrangé 2017-02-07 14:13:31 UTC

Upstream fix in git master is

commit c8583fd3783c5b811590fcb7bae4ce6e7344963e
Author: Daniel P. Berrange <berrange>
Date:   Thu Feb 2 18:18:48 2017 +0000

    Correctly validate color map range indexes
    
    The color map index could wrap around to zero causing negative
    array index accesses.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=778050
    
    CVE-2017-5885
    
    Signed-off-by: Daniel P. Berrange <berrange>

Comment 9 errata-xmlrpc 2017-08-01 19:57:10 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2017:2258 https://access.redhat.com/errata/RHSA-2017:2258