#VU45307 Input validation error in PHP - CVE-2011-0420

Vulnerability identifier: #VU45307

Vulnerability risk: Medium

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

CVE-ID: CVE-2011-0420

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
PHP
Universal components / Libraries / Scripting languages

Vendor: PHP Group

Description

The vulnerability allows context-dependent attackers to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient validation of user-supplied input. A remote attacker can cause a denial of service (crash) via an invalid size argument, which triggers a NULL pointer dereference.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

PHP: 5.3.5

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External links
https://lists.apple.com/archives/Security-announce/2011//Oct/msg00003.html
https://securityreason.com/achievement_securityalert/94
https://securityreason.com/securityalert/8087
https://support.apple.com/kb/HT5002
https://svn.php.net/viewvc/php/php-src/trunk/ext/intl/grapheme/grapheme_string.c?r1=306449&r2=306448&pathrev=306449
https://www.debian.org/security/2011/dsa-2266
https://www.exploit-db.com/exploits/16182
https://www.kb.cert.org/vuls/id/210829
https://www.securityfocus.com/archive/1/516504/100/0/threaded
https://www.securityfocus.com/archive/1/516518/100/0/threaded
https://www.securityfocus.com/bid/46429
https://exchange.xforce.ibmcloud.com/vulnerabilities/65437

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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.