Bug 1339949 (CVE-2016-5096)

Summary: CVE-2016-5096 php: Integer underflow causing arbitrary null write in fread/gzread
Product: [Other] Security Response Reporter: Adam Mariš <amaris>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED ERRATA QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: abhgupta, dmcphers, fedora, hhorak, jialiu, jokerman, jorton, kseifried, lmeyer, mmccomas, rcollet, tiwillia, webstack-team
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: php 5.5.36, php 5.6.22 Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2016-06-07 11:34:42 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On: 1339950    
Bug Blocks: 1339953    

Description Adam Mariš 2016-05-26 09:04:56 UTC
An integer underflow resulting into arbitrary null character write in fread/gzread function was found.

Upstream bug:

https://bugs.php.net/bug.php?id=72114

Upstream patch:

https://git.php.net/?p=php-src.git;a=commit;h=abd159cce48f3e34f08e4751c568e09677d5ec9c

CVE request:

http://seclists.org/oss-sec/2016/q2/404

Comment 1 Adam Mariš 2016-05-26 09:08:33 UTC
Created php tracking bugs for this issue:

Affects: fedora-all [bug 1339950]

Comment 2 Fedora Update System 2016-05-29 22:21:17 UTC
php-5.6.22-1.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report.

Comment 3 Fedora Update System 2016-05-30 21:20:44 UTC
php-5.6.22-1.fc24 has been pushed to the Fedora 24 stable repository. If problems still persist, please make note of it in this bug report.

Comment 4 Fedora Update System 2016-06-03 15:21:44 UTC
php-5.6.22-1.fc22 has been pushed to the Fedora 22 stable repository. If problems still persist, please make note of it in this bug report.

Comment 5 Tomas Hoger 2016-06-07 11:34:42 UTC
This problem occurs when fread or gzread are called with excessively large $length argument value (above 2GB / 2^31).  Additionally, this flaw can only be triggered when PHP is running with no memory limit, or its memory limit exceeds 2GB.  The default configuration of PHP packages in Red Hat products sets memory_limit to 128M, completely blocking this issue.

This issue can be mitigated by ensuring memory_limit is set and its value does not exceed 2GB.

Comment 6 errata-xmlrpc 2016-11-15 11:53:15 UTC
This issue has been addressed in the following products:

  Red Hat Software Collections for Red Hat Enterprise Linux 6
  Red Hat Software Collections for Red Hat Enterprise Linux 6.7 EUS
  Red Hat Software Collections for Red Hat Enterprise Linux 7
  Red Hat Software Collections for Red Hat Enterprise Linux 7.2 EUS
  Red Hat Software Collections for Red Hat Enterprise Linux 7.3 EUS

Via RHSA-2016:2750 https://rhn.redhat.com/errata/RHSA-2016-2750.html