CVE-2015-6835 Use after free in n/a

Critical 9.8 Published 16 May 2016 Updated 6 Aug 2024

Remote attackers can execute arbitrary code or cause denial of service via crafted session content due to a use-after-free in PHP's session deserializer.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2015-6835?

CVE-2015-6835 is a critical use after free vulnerability in Php Php, published on 16 May 2016. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

The session deserializer in PHP before 5.4.45, 5.5.x before 5.5.29, and 5.6.x before 5.6.13 mishandles multiple php_var_unserialize calls, which allow remote attackers to execute arbitrary code or cause a denial of service (use-after-free) via crafted session content.

Which versions are affected by CVE-2015-6835?

It affects 1 product.

Products include Php Php.

How do I fix CVE-2015-6835?

Upgrade to a fixed version.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2015-6835 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2015-6835 exists.

Public exploit code: 1 Exploit-DB entry and 1 proofs of concept on GitHub.

All Php Php vulnerabilities

Sources

Also known as GHSA-5qpr-hcf2-vwc2, UBUNTU-CVE-2015-6835.