CVE-2015-6835: Use After Free

Published May 16, 2016
·
Updated

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 phpvarunserialize calls, which allow remote attackers to execute arbitrary code or cause a denial of service (use-after-free) via crafted session content.

Affected Software

63 affected components
PHP PHP=5.6.0-alpha1
PHP PHP=5.6.0-alpha2
PHP PHP=5.6.0-alpha3
PHP PHP=5.6.0-alpha4
PHP PHP=5.6.0-alpha5
PHP PHP=5.6.0-beta1
PHP PHP=5.6.0-beta2
PHP PHP=5.6.0-beta3
PHP PHP=5.6.0-beta4
PHP PHP=5.6.1
PHP PHP=5.6.2
PHP PHP=5.6.3
PHP PHP=5.6.4
PHP PHP=5.6.5
PHP PHP=5.6.6
PHP PHP=5.6.7
PHP PHP=5.6.8
PHP PHP=5.6.9
PHP PHP=5.6.10
PHP PHP=5.6.11
PHP PHP=5.6.12
PHP PHP<=5.4.44
PHP PHP=5.5.0
PHP PHP=5.5.0-alpha1
PHP PHP=5.5.0-alpha2
PHP PHP=5.5.0-alpha3
PHP PHP=5.5.0-alpha4
PHP PHP=5.5.0-alpha5
PHP PHP=5.5.0-alpha6
PHP PHP=5.5.0-beta1
PHP PHP=5.5.0-beta2
PHP PHP=5.5.0-beta3
PHP PHP=5.5.0-beta4
PHP PHP=5.5.0-rc1
PHP PHP=5.5.0-rc2
PHP PHP=5.5.1
PHP PHP=5.5.2
PHP PHP=5.5.3
PHP PHP=5.5.4
PHP PHP=5.5.5
PHP PHP=5.5.6
PHP PHP=5.5.7
PHP PHP=5.5.8
PHP PHP=5.5.9
PHP PHP=5.5.10
PHP PHP=5.5.11
PHP PHP=5.5.12
PHP PHP=5.5.13
PHP PHP=5.5.14
PHP PHP=5.5.15
PHP PHP=5.5.16
PHP PHP=5.5.17
PHP PHP=5.5.18
PHP PHP=5.5.19
PHP PHP=5.5.20
PHP PHP=5.5.21
PHP PHP=5.5.22
PHP PHP=5.5.23
PHP PHP=5.5.24
PHP PHP=5.5.25
PHP PHP=5.5.26
PHP PHP=5.5.27
PHP PHP=5.5.28

Event History

May 16, 2016
CVE Published
via MITRE·10:00 AM
Data Sourced
via MITRE·10:00 AM
Description

Frequently Asked Questions

1

What is the severity of CVE-2015-6835?

CVE-2015-6835 has a high severity as it allows remote attackers to execute arbitrary code or cause denial of service through crafted session content.

2

How do I fix CVE-2015-6835?

To fix CVE-2015-6835, upgrade your PHP installation to version 5.4.45, 5.5.29, or 5.6.13 or later.

3

What software versions are affected by CVE-2015-6835?

CVE-2015-6835 affects PHP versions prior to 5.4.45, 5.5.x before 5.5.29, and 5.6.x before 5.6.13.

4

What type of attacks can result from CVE-2015-6835?

CVE-2015-6835 can lead to remote code execution and denial of service attacks due to session deserialization vulnerabilities.

5

Is CVE-2015-6835 exploitable remotely?

Yes, CVE-2015-6835 is exploitable remotely, allowing attackers to execute code on vulnerable PHP servers.

Contact

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Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
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