Quantum Secular Labs / Blog / Advisories

CVE-2006-4812: PHP: Buffer overflow

CVE-2006-4812 has a CVSS v2 base score of 10.0 (the maximum on that scale) and affects PHP. Per its scoring, it can be exploited over the network, without authentication. The scored impact on confidentiality, integrity and availability is the highest available.

Vulnerability description

Integer overflow in PHP 5 up to 5.1.6 and 4 before 4.3.0 allows remote attackers to execute arbitrary code via an argument to the unserialize PHP function with a large value for the number of array elements, which triggers the overflow in the Zend Engine ecalloc function (Zend/zend_alloc.c).

Severity breakdown

CVSS v2.0 10.0: AV:N/AC:L/Au:N/C:C/I:C/A:C

Access vector: Network. Exploitable remotely over the network.
Access complexity: Low. No special conditions are required.
Authentication: None. No authentication is needed.
Confidentiality impact: Complete. Total information disclosure.
Integrity impact: Complete. Total loss of integrity.
Availability impact: Complete. Total shutdown of the component.

Underlying weakness

CWE-94: Improper Control of Generation of Code

The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.

Affected products

PHP: 4.0; 4.0.1; 4.0.1 patch1; 4.0.1 patch2; 4.0.2; 4.0.3; 4.0.3 patch1; 4.0.4; 4.0.5; 4.0.6; 4.0.7; 4.0.7 rc1