Vulnerability record · CVE-2013-6420 · published 17 December 2013
CVE-2013-6420: Php memory buffer overflow vulnerability
Php · Php
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, which allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted certificate that is not properly handled by the openssl_x509_parse function.
Description
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, which allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a crafted certificate that is not properly handled by the openssl_x509_parse function.
AV:N/AC:L/Au:N/C:P/I:P/A:P
Affected products
3 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
Track CVE-2013-6420 inside VULONE
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2013-6420), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.
