CVE-2016-6296

Severity: critical (CVSS 9.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 6.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2016-07-25 · updated 2026-06-17
Weakness: CWE-119

Description

Integer signedness error in the simplestring_addn function in simplestring.c in xmlrpc-epi through 0.54.2, as used in PHP before 5.5.38, 5.6.x before 5.6.24, and 7.x before 7.0.9, allows remote attackers to cause a denial of service (heap-based buffer overflow) or possibly have unspecified other impact via a long first argument to the PHP xmlrpc_encode_request function.

Affected products

PHP: through 5.5.37; 5.6.0-alpha1, 5.6.0-alpha2, 5.6.0-alpha3, 5.6.0-alpha4, 5.6.0-alpha5, 5.6.0-beta1 (+33)

References

http://git.php.net/?p=php-src.git%3Ba=commit%3Bh=e6c48213c22ed50b2b987b479fcc1ac709394caa
http://lists.apple.com/archives/security-announce/2016/Sep/msg00006.html
http://openwall.com/lists/oss-security/2016/07/24/2
http://php.net/ChangeLog-5.php
http://php.net/ChangeLog-7.php
http://rhn.redhat.com/errata/RHSA-2016-2750.html
http://www.debian.org/security/2016/dsa-3631
http://www.securityfocus.com/bid/92095
http://www.securitytracker.com/id/1036430
http://www.ubuntu.com/usn/USN-3059-1
https://bugs.php.net/72606
https://lists.debian.org/debian-lts-announce/2019/11/msg00029.html

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