Bug 1416704 (CVE-2017-5618)

Summary: CVE-2017-5618 screen: Privilege escalation via unsafe logfile handling
Product: [Other] Security Response Reporter: Andrej Nemec <anemec>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED NOTABUG QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: jridky, lnykryn, pdwyer, phracek
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2017-01-26 16:43:49 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:    
Bug Blocks: 1416707    

Description Andrej Nemec 2017-01-26 09:49:40 UTC
A vulnerability was found in a way screen handles logfiles. A maliciously crafted logfile could allow the attacker to possibly elevate his privileges to those of root.

References:

https://lists.gnu.org/archive/html/screen-devel/2017-01/msg00025.html
http://seclists.org/oss-sec/2017/q1/184

Comment 1 Cedric Buissart 2017-01-26 16:42:13 UTC
The vulnerable code is not present in screen as shipped in Red Hat Enterprise Linux versions 5, 6 and 7.

Also, Red Hat Enterprise Linux versions 5, 6 and 7 are shipped with /usr/bin/screen SGID set to 'screen' group.

Comment 2 Andrej Nemec 2017-01-30 09:37:36 UTC
CVE assignment:

http://seclists.org/oss-sec/2017/q1/224