Buffer overflow in PHP - CVE-2013-6420
Published: November 27, 2018 / Updated: April 7, 2020
Vulnerability identifier: #VU16076
CSH Severity: High
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Amber
CVE-ID: CVE-2013-6420
CWE-ID: CWE-119
Exploitation vector: Remote access
Exploit availability:
Public exploit is available
Vendor: PHP Group
Affected software:
PHP
PHP
Detailed vulnerability description
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a boundary error when the asn1_time_to_time_t function in ext/openssl/openssl.c in PHP before 5.3.28, 5.4.x before 5.4.23, and 5.5.x before 5.5.7 does not properly parse (1) notBefore and (2) notAfter timestamps in X.509 certificates. A remote attacker can supply specially crafted X.509 certificates, trigger memory corruption and cause the service to crash or execute arbitrary code on the target system.
Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.
How to mitigate CVE-2013-6420
Install updates from vendor's website.