#VU110317 Permissions, Privileges, and Access Controls in PHP - CVE-2009-4018

Vulnerability identifier: #VU110317

Vulnerability risk: Medium

CVSSv4.0: 5.5 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2009-4018

CWE-ID: CWE-264

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
PHP
Universal components / Libraries / Scripting languages

Vendor: PHP Group

Description

The vulnerability allows a remote non-authenticated attacker to read and manipulate data.

The proc_open function in ext/standard/proc_open.c in PHP before 5.2.11 and 5.3.x before 5.3.1 does not enforce the (1) safe_mode_allowed_env_vars and (2) safe_mode_protected_env_vars directives, which allows context-dependent attackers to execute programs with an arbitrary environment via the env parameter, as demonstrated by a crafted value of the LD_LIBRARY_PATH environment variable.

Mitigation
Install update from vendor's website.

Vulnerable software versions

PHP: 1.0, 2.0, 2.0b10, 3.0, 3.0.1, 3.0.2, 3.0.3, 3.0.4, 3.0.5, 3.0.6, 3.0.7, 3.0.8, 3.0.9, 3.0.10, 3.0.11, 3.0.12, 3.0.13, 3.0.14, 3.0.15, 3.0.16, 3.0.17, 3.0.18, 4.0, 4.0.0, 4.0.1, 4.0.2, 4.0.3, 4.0.4, 4.0.5, 4.0.6, 4.0.7, 4.1, 4.1.1, 4.1.2, 4.2, 4.2.1, 4.2.2, 4.2.3, 4.3, 4.3.1, 4.3.2, 4.3.3, 4.3.4, 4.3.5, 4.3.6, 4.3.7, 4.3.8, 4.3.9, 4.3.10, 4.3.11, 4.4, 4.4.1, 4.4.2, 4.4.3, 4.4.4, 4.4.5, 4.4.6, 4.4.7, 4.4.8, 4.4.9, 5, 5.0.0, 5.0.1, 5.0.2, 5.0.3, 5.0.4, 5.0.5, 5.1.0, 5.1.1, 5.1.2, 5.1.3, 5.1.4, 5.1.5, 5.1.6, 5.2, 5.2.2, 5.2.4, 5.2.6, 5.2.7, 5.2.8, 5.2.9, 5.3

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External links
https://bugs.php.net/bug.php?id=49026
https://marc.info/?l=bugtraq&m=127680701405735&w=2
https://marc.info/?l=oss-security&m=125886770008678&w=2
https://marc.info/?l=oss-security&m=125897935330618&w=2
https://secunia.com/advisories/40262
https://secunia.com/advisories/41480
https://secunia.com/advisories/41490
https://svn.php.net/viewvc/?view=revision&revision=286360
https://svn.php.net/viewvc/php/php-src/branches/PHP_5_2/ext/standard/proc_open.c?r1=286360&r2=286359&pathrev=286360
https://svn.php.net/viewvc/php/php-src/branches/PHP_5_3/ext/standard/proc_open.c?r1=286360&r2=286359&pathrev=286360
https://www.itrc.hp.com/service/cki/docDisplay.do?docId=emr_na-c02512995
https://www.mandriva.com/security/advisories?name=MDVSA-2009:303
https://www.openwall.com/lists/oss-security/2009/11/23/15
https://www.php.net/ChangeLog-5.php
https://www.securityfocus.com/bid/37138
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A7256

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.