Internet Bug Bounty: Heap Use After Free in unserialize()

2017-08-1813:24:49

cy1337

hackerone.com

7.5 High

CVSS3

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

NONE

Integrity Impact

HIGH

Availability Impact

NONE

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

5 Medium

CVSS2

Access Vector

NETWORK

Access Complexity

LOW

Authentication

NONE

Confidentiality Impact

NONE

Integrity Impact

PARTIAL

Availability Impact

NONE

AV:N/AC:L/Au:N/C:N/I:P/A:N

0.003 Low

EPSS

Percentile

64.8%

JSON

ext/standard/var_unserializer.re in PHP 7.0.x before 7.0.21 and 7.1.x before 7.1.7 is prone to a heap use after free while unserializing untrusted data, related to the zval_get_type function in Zend/zend_types.h. Exploitation of this issue can have an unspecified impact on the integrity of PHP.

This has been fixed and assigned CVE-2017-12934. The bug report is here: https://bugs.php.net/bug.php?id=74101