CVE-2016-4538

9.8 CRITICAL
Published: May 22, 2016 Modified: May 06, 2026
View on NVD

Description

The bcpowmod function in ext/bcmath/bcmath.c in PHP before 5.5.35, 5.6.x before 5.6.21, and 7.x before 7.0.6 modifies certain data structures without considering whether they are copies of the _zero_, _one_, or _two_ global variable, which allows remote attackers to cause a denial of service or possibly have unspecified other impact via a crafted call.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
http://lists.fedoraproject.org/pipermail/package-announce/2016-May/183736.html
Source: security@debian.org
http://lists.opensuse.org/opensuse-updates/2016-05/msg00086.html
Source: security@debian.org
http://lists.opensuse.org/opensuse-updates/2016-06/msg00027.html
Source: security@debian.org
http://php.net/ChangeLog-5.php
Source: security@debian.org
Patch
http://php.net/ChangeLog-7.php
Source: security@debian.org
Patch
http://rhn.redhat.com/errata/RHSA-2016-2750.html
Source: security@debian.org
http://www.debian.org/security/2016/dsa-3602
Source: security@debian.org
http://www.openwall.com/lists/oss-security/2016/05/05/21
Source: security@debian.org
http://www.securityfocus.com/bid/90173
Source: security@debian.org
https://bugs.php.net/bug.php?id=72093
Source: security@debian.org
Exploit
https://git.php.net/?p=php-src.git%3Ba=commit%3Bh=d650063a0457aec56364e4005a636dc6c401f9cd
Source: security@debian.org
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05240731
Source: security@debian.org
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05320149
Source: security@debian.org
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05390722
Source: security@debian.org
https://security.gentoo.org/glsa/201611-22
Source: security@debian.org
http://lists.fedoraproject.org/pipermail/package-announce/2016-May/183736.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://lists.opensuse.org/opensuse-updates/2016-05/msg00086.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://lists.opensuse.org/opensuse-updates/2016-06/msg00027.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://php.net/ChangeLog-5.php
Source: af854a3a-2127-422b-91ae-364da2661108
Patch
http://php.net/ChangeLog-7.php
Source: af854a3a-2127-422b-91ae-364da2661108
Patch
http://rhn.redhat.com/errata/RHSA-2016-2750.html
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.debian.org/security/2016/dsa-3602
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.openwall.com/lists/oss-security/2016/05/05/21
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.securityfocus.com/bid/90173
Source: af854a3a-2127-422b-91ae-364da2661108
https://bugs.php.net/bug.php?id=72093
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit
https://git.php.net/?p=php-src.git%3Ba=commit%3Bh=d650063a0457aec56364e4005a636dc6c401f9cd
Source: af854a3a-2127-422b-91ae-364da2661108
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05240731
Source: af854a3a-2127-422b-91ae-364da2661108
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05320149
Source: af854a3a-2127-422b-91ae-364da2661108
https://h20566.www2.hpe.com/portal/site/hpsc/public/kb/docDisplay?docId=emr_na-c05390722
Source: af854a3a-2127-422b-91ae-364da2661108
https://security.gentoo.org/glsa/201611-22
Source: af854a3a-2127-422b-91ae-364da2661108

30 reference(s) from NVD

Quick Stats

CVSS v3 Score
9.8 / 10.0
EPSS (Exploit Probability)
6.5%
91th percentile
Exploitation Status
Not in CISA KEV

Weaknesses (CWE)

CWE-20

Affected Vendors

opensuse fedoraproject php

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