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CVE-2013-6420: 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....

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.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysis

Security readout for executives and security teams

CVE-2013-6420 is an old PHP OpenSSL parsing flaw. A specially crafted X.509 certificate could corrupt memory when vulnerable PHP versions parse certificate dates, potentially crashing the service or enabling code execution. Business urgency is highest for legacy PHP systems that still process user-supplied certificates. Exposure is most plausible on unsupported legacy PHP 5.3, 5.4, or 5.5 deployments, especially applications that call openssl_x509_parse on certificates supplied by users, partners, APIs, or mail/TLS-processing workflows. Evidence does not identify current maintained PHP branches as affected. Prioritize remediation if any internet-facing or partner-facing legacy PHP service parses certificates. For modern supported PHP environments, this is mainly an inventory and legacy-retirement concern rather than a broad emergency. Mitigation focus: Upgrade PHP to versions including the vendor fix or newer supported releases.; Apply distro or product security updates from Debian, Red Hat, Ubuntu, SUSE, Apple, or HP as applicable.; Inventory applications that parse uploaded or remote X.509 certificates..

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Severity
Unknown
CVSS
Not scored
Known Exploited
No
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Official CVE source material

CNA and ADP enrichment extracted from CVE v5

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