critical
9.8
CWE
416
Advisory Published
Updated

CVE-2015-6835: Use After Free

First published: Mon 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 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.

Credit: meissner@suse.de

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

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Reference Links

Frequently Asked Questions

  • 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.

  • 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.

  • 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.

  • 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.

  • Is CVE-2015-6835 exploitable remotely?

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

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