CVE-2015-8994

An issue was discovered in PHP 5.x and 7.x, when the configuration uses apache2handler/mod_php or php-fpm with OpCache enabled. With 5.x after 5.6.28 or 7.x after 7.0.13, the issue is resolved in a non-default configuration with the opcache.validate_permission=1 setting. The vulnerability details are as follows. In PHP SAPIs where PHP interpreters share a common parent process, Zend OpCache creates a shared memory object owned by the common parent during initialization. Child PHP processes inherit the SHM descriptor, using it to cache and retrieve compiled script bytecode ("opcode" in PHP jargon). Cache keys vary depending on configuration, but filename is a central key component, and compiled opcode can generally be run if a script's filename is known or can be guessed. Many common shared-hosting configurations change EUID in child processes to enforce privilege separation among hosted users (for example using mod_ruid2 for the Apache HTTP Server, or php-fpm user settings). In these scenarios, the default Zend OpCache behavior defeats script file permissions by sharing a single SHM cache among all child PHP processes. PHP scripts often contain sensitive information: Think of CMS configurations where reading or running another user's script usually means gaining privileges to the CMS database.
Configurations

Configuration 1 (hide)

OR cpe:2.3:a:php:php:*:*:*:*:*:*:*:*
cpe:2.3:a:php:php:*:*:*:*:*:*:*:*

History

21 Nov 2024, 02:39

Type Values Removed Values Added
References () http://marc.info/?l=php-internals&m=147876797317925&w=2 - Mailing List () http://marc.info/?l=php-internals&m=147876797317925&w=2 - Mailing List
References () http://marc.info/?l=php-internals&m=147921016724565&w=2 - Mailing List () http://marc.info/?l=php-internals&m=147921016724565&w=2 - Mailing List
References () http://openwall.com/lists/oss-security/2017/02/28/1 - Mailing List () http://openwall.com/lists/oss-security/2017/02/28/1 - Mailing List
References () http://seclists.org/oss-sec/2016/q4/343 - Mailing List, Third Party Advisory () http://seclists.org/oss-sec/2016/q4/343 - Mailing List, Third Party Advisory
References () http://seclists.org/oss-sec/2017/q1/520 - Mailing List, Third Party Advisory () http://seclists.org/oss-sec/2017/q1/520 - Mailing List, Third Party Advisory
References () https://bugs.php.net/bug.php?id=69090 - Exploit, Issue Tracking () https://bugs.php.net/bug.php?id=69090 - Exploit, Issue Tracking
References () https://ma.ttias.be/a-better-way-to-run-php-fpm/ - Exploit, Technical Description, Third Party Advisory () https://ma.ttias.be/a-better-way-to-run-php-fpm/ - Exploit, Technical Description, Third Party Advisory

Information

Published : 2017-03-02 06:59

Updated : 2024-11-21 02:39


NVD link : CVE-2015-8994

Mitre link : CVE-2015-8994

CVE.ORG link : CVE-2015-8994


JSON object : View

Products Affected

php

  • php
CWE
CWE-264

Permissions, Privileges, and Access Controls