Bug 1438700 – CVE-2017-7394 tigervnc: Server crash via long usernames

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Bug 1438700 - (CVE-2017-7394) CVE-2017-7394 tigervnc: Server crash via long usernames

Summary:	CVE-2017-7394 tigervnc: Server crash via long usernames

Status:	NEW

Aliases:	CVE-2017-7394

Product:	Security Response
Classification:	Other
Component:	vulnerability (Show other bugs)
Sub Component:
Version:	unspecified
Hardware:	All Linux

Priority	medium Severity medium
Target Milestone:	---
Target Release:	---
Assigned To:	Red Hat Product Security
QA Contact:
Docs Contact:

URL:
Whiteboard:	impact=moderate,public=20170329,repor...
Keywords:	Security

Depends On:	1438704 1438737
Blocks:	1415638 1438705
	Show dependency tree / graph

Reported:	2017-04-04 04:45 EDT by Andrej Nemec
Modified:	2018-03-29 18:02 EDT (History)
CC List:	4 users (show)

See Also:
Fixed In Version:
Doc Type:	If docs needed, set a value
Doc Text:	A missing input sanitization flaw was found in the way TigerVNC handled credentials. A remote unauthenticated attacker could use this flaw to make Xvnc crash by sending specially crafted usernames, resulting in denial of service.
Story Points:	---
Clone Of:
Environment:
Last Closed:
Type:	---
Regression:	---
Mount Type:	---
Documentation:	---
CRM:
Verified Versions:
Category:	---
oVirt Team:	---
RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---

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External Trackers
Tracker	ID	Priority	Status	Summary	Last Updated
Red Hat Product Errata	RHSA-2017:2000	normal	SHIPPED_LIVE	Moderate: tigervnc and fltk security, bug fix, and enhancement update	2017-08-01 14:33:08 EDT

Groups: None (edit)

Description Andrej Nemec 2017-04-04 04:45:51 EDT

In TigerVNC (SSecurityPlain.cxx SSecurityPlain::processMsg), unauthenticated users can crash the server by sending long usernames. 

Upstream patches:

https://github.com/TigerVNC/tigervnc/pull/440/commits/62197c89e98be47a174074e4c7429c57767a4929
https://github.com/TigerVNC/tigervnc/pull/440/commits/9801c5efcf8c1774d9c807ebd5d27ac7049ad993

Comment 1 Andrej Nemec 2017-04-04 04:54:30 EDT

Created tigervnc tracking bugs for this issue:

Affects: fedora-all [bug 1438704]

Comment 4 errata-xmlrpc 2017-08-01 16:51:50 EDT

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2017:2000 https://access.redhat.com/errata/RHSA-2017:2000

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