Deserialization of untrusted data in PHP - CVE-2017-12933
Published: January 9, 2018 / Updated: January 11, 2018
Vulnerability identifier: #VU9956
CSH Severity: Low
CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2017-12933
CWE-ID: CWE-502
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a buffer over-read while unserializing untrusted data in the finish_nested_data function in ext/standard/var_unserializer.re. A remote attacker can perform a denial of service attack.
Affected software
PHP
Debian Linux
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for Power
php5 (Ubuntu package)
php (Debian package)
Debian Linux
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for Power
php5 (Ubuntu package)
php (Debian package)
How to mitigate CVE-2017-12933
The vendor has issued the following versions to address this vulnerability: 5.6.31, 7.0.21, 7.1.7.
php5 (Ubuntu package) - update to 5.5.9+dfsg-1ubuntu4.23
php (Debian package) - update to 5.6.33+dfsg-0+deb8u1
php (Debian package) - update to 5.6.33+dfsg-0+deb8u1