CVE-2013-6420

highpriority · attend · 52EPSS 0.356 · 98 %ileexploit · PoCDEEURUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

1 exploit · PoC

Likely / severe?

35.6% (98th) EPSS

CVSS 7.5 · high

Is it mine?

118 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.6–7.5

v2.07.5highAV:N/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 10 · impact 6.4

v2.06.8mediumAV:N/AC:L/Au:N/C:P/I:P/A:P/E:POCsecondary · CVSS-BT (t0sche)

v3.15.6mediumAV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondary · FSTEC (BDU) RU

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-119USprimaryCWE-119US

exploits (1)

Public proof-of-concept and weaponised exploit code.

EDB-30395PHP - 'openssl_x509_parse()' Memory CorruptionPoC · exploit_db

affected products (118)

Products and version ranges known to be affected.

Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Juniper JUNOSall versionscert_bundDEcpe:/o:juniper:junos:-
Mandriva Linuxall versionscert_bundDEcpe:/o:mandriva:linux:-
Open Source PHPall versionscert_bundDEcpe:/a:php:php:-
Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
Red Hat Enterprise Linux 5all versionscert_bundDEcpe:/o:redhat:enterprise_linux:5
Red Hat Enterprise Linux Desktop 5all versionscert_bundDEcpe:/o:redhat:enterprise_linux_desktop:5
Red Hat Enterprise Linux Desktop 6all versionscert_bundDEcpe:/o:redhat:enterprise_linux_desktop:6
Red Hat Enterprise Linux HPC Node 6all versionscert_bundDEcpe:/o:redhat:enterprise_linux_hpc_node:6
Red Hat Enterprise Linux Resilient Storage EUS 6.5.zall versionscert_bundDEcpe:/o:redhat:enterprise_linux:6.5.z:resilentstorage:eus
Red Hat Enterprise Linux Server 6all versionscert_bundDEcpe:/o:redhat:enterprise_linux:6:server
Red Hat Enterprise Linux Server EUS 6.5.zall versionscert_bundDEcpe:/o:redhat:enterprise_linux:6.5.z:server:eus
Red Hat Enterprise Linux Workstation 6all versionscert_bundDEcpe:/o:redhat:enterprise_linux_workstation:6
SUSE Linuxall versionscert_bundDEcpe:/o:suse:suse_linux:-
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
n/a n/a≤ n/aenisa_euvdEU
Canonical Ltd. Ubuntu≤ 13.04fstec_bduRU
Canonical Ltd. Ubuntu≤ 12.10fstec_bduRU
Canonical Ltd. Ubuntu≤ 13.10fstec_bduRU
Canonical Ltd. Ubuntu≤ 10.04fstec_bduRU

showing 20 of 118

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2023-1283PHP: Schwachstelle ermöglicht Ausführen von beliebigem Programmcode mit den Rechten des DienstesDeutsch2013-12-10csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann eine Schwachstelle in PHP ausnutzen, um beliebigen Programmcode mit den Rechten des Dienstes auszuführen oder um einen Denial of Service Zustand herbeizuführen.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund NVD CVE.org MITRE

published 2013-12-17modified 2026-06-17

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Related entries.

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+21023 more

references (45)

External citations — patches, advisories, analysis.

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