Input validation error in PHP

1) Input validation error

EUVDB-ID: #VU32831

Risk: Medium

CVSSv4.0: 6.9 [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:A/U:Green]

CVE-ID: CVE-2011-4885

CWE-ID: CWE-20 - Improper input validation

Exploit availability: Yes

Description

The vulnerability allows a remote non-authenticated attacker to perform service disruption.

PHP before 5.3.9 computes hash values for form parameters without restricting the ability to trigger hash collisions predictably, which allows remote attackers to cause a denial of service (CPU consumption) by sending many crafted parameters.

Mitigation

Install update from vendor's website.

Vulnerable software versions

PHP: 5.3.0 - 5.3.8

CPE2.3

• cpe:2.3:a:php_group:php:5.3.8:*:*:*:*:*:*:*

External links

https://archives.neohapsis.com/archives/bugtraq/2011-12/0181.html
https://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c03360041
https://lists.apple.com/archives/security-announce/2012/May/msg00001.html
https://lists.opensuse.org/opensuse-security-announce/2012-03/msg00013.html
https://lists.opensuse.org/opensuse-security-announce/2012-03/msg00016.html
https://marc.info/?l=bugtraq&m=132871655717248&w=2
https://marc.info/?l=bugtraq&m=133469208622507&w=2
https://rhn.redhat.com/errata/RHSA-2012-0071.html
https://secunia.com/advisories/47404
https://secunia.com/advisories/48668
https://support.apple.com/kb/HT5281
https://svn.php.net/viewvc?view=revision&revision=321003
https://svn.php.net/viewvc?view=revision&revision=321040
https://www.debian.org/security/2012/dsa-2399
https://www.exploit-db.com/exploits/18296
https://www.exploit-db.com/exploits/18305
https://www.kb.cert.org/vuls/id/903934
https://www.mandriva.com/security/advisories?name=MDVSA-2011:197
https://www.mandriva.com/security/advisories?name=MDVSA-2013:150
https://www.nruns.com/_downloads/advisory28122011.pdf
https://www.ocert.org/advisories/ocert-2011-003.html
https://www.oracle.com/technetwork/topics/security/cpujul2012-392727.html
https://www.redhat.com/support/errata/RHSA-2012-0019.html
https://www.securityfocus.com/bid/51193
https://www.securitytracker.com/id?1026473
https://exchange.xforce.ibmcloud.com/vulnerabilities/72021
https://github.com/FireFart/HashCollision-DOS-POC/blob/master/HashtablePOC.py

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, a fully functional exploit for this vulnerability is available.