Bug 959433 (CVE-2015-7810)

Summary: CVE-2015-7810 libbluray (MountManager): TOCTOU race when expanding JAR files
Product: [Other] Security Response Reporter: Jan Lieskovsky <jlieskov>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED WONTFIX QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: bnocera, carnil, dkholia, fweimer, security-response-team
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2016-06-01 09:33:26 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: 959238    
Bug Blocks: 959437    

Description Jan Lieskovsky 2013-05-03 13:14:56 UTC 
A time-of-check time-of-use (TOCTOU) race condition flaw was found in the way the MountManager class implementation of libbluray, a library to access Blu-Ray disks for video playback, performed expansion of JAR archives / files. A local attacker, with write privilege (in)to a directory, where MountManager class performed JAR files expansion, could use this flaw to conduct symbolic link attacks (possibly leading to their ability to [recursively] delete or overwrite arbitrary directory, accessible with the privileges of the user running the application utilizing the libbluray library).

This issue was discovered by Florian Weimer of Red Hat Product Security Team.
Comment 1 Jan Lieskovsky 2013-05-03 13:17:10 UTC 
This issue affects the versions of the libbluray package, as shipped with Fedora release of 17, 18, and Fedora EPEL-6.
Comment 2 Kurt Seifried 2015-02-23 02:32:42 UTC 
From the original report by Florian Weimer:

Creating a temporary file, deleting it, and re-creating it as a directory is racy:

        File tmpDir = null;
        try {
            jar = new JarFile(path);
            tmpDir = File.createTempFile("bdj-", "");
        } catch (IOException e) {
            e.printStackTrace();
            throw new MountException();
        }
        
        // create temporary directory
        tmpDir.delete();
        tmpDir.mkdir();

Another user might create a directory with wide permissions and do nasty stuff in there.
Comment 3 Adam Mariš 2015-11-03 12:49:30 UTC 
CVE was assigned:

http://seclists.org/oss-sec/2015/q4/70