CVE-2017-12933

Severity: critical (CVSS 9.8 v3.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 6.9% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2017-08-18 · updated 2026-06-17
Weakness: CWE-125

Description

The finish_nested_data function in ext/standard/var_unserializer.re in PHP before 5.6.31, 7.0.x before 7.0.21, and 7.1.x before 7.1.7 is prone to a buffer over-read while unserializing untrusted data. Exploitation of this issue can have an unspecified impact on the integrity of PHP.

Affected products

PHP: through 5.6.30; 7.0.0, 7.0.1, 7.0.2, 7.0.3, 7.0.4, 7.0.5 (+22)

References

http://php.net/ChangeLog-5.php
http://php.net/ChangeLog-7.php
http://www.securityfocus.com/bid/99490
https://access.redhat.com/errata/RHSA-2018:1296
https://bugs.php.net/bug.php?id=74111
https://usn.ubuntu.com/3566-1/
https://usn.ubuntu.com/3566-2/
https://www.debian.org/security/2018/dsa-4080
https://www.debian.org/security/2018/dsa-4081
http://php.net/ChangeLog-5.php
http://php.net/ChangeLog-7.php
http://www.securityfocus.com/bid/99490

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