VDB-77709 · CVE-2015-6835 · BID 76734

PHP up to 5.4.44/5.5.28/5.6.12 Session Deserializer use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.4$0-$5k0.00

A vulnerability, which was classified as critical, was found in PHP up to 5.4.44/5.5.28/5.6.12 (Programming Language Software). This affects some unknown functionality of the component Session Deserializer. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability.

The weakness was shared 09/03/2015 by Taoguang Chen as Version 5.6.13 as confirmed changelog entry (Website). The advisory is shared at secure.php.net. This vulnerability is uniquely identified as CVE-2015-6835 since 09/08/2015. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 86654 (Mac OS X < 10.11.1 Multiple Vulnerabilities), which helps to determine the existence of the flaw in a target environment. It is assigned to the family MacOS X Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 11628 (PHP Versions Prior to 5.6.13/5.5.29/5.4.45 Multiple Vulnerabilities).

Upgrading to version 5.4.45, 5.5.29 or 5.6.13 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (86654). The entries 67396, 67398, 67420 and 67724 are related to this item.

Productinfo

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License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.4

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 86654
Nessus Name: Mac OS X < 10.11.1 Multiple Vulnerabilities
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍

OpenVAS ID: 14611
OpenVAS Name: Amazon Linux Local Check: alas-2016-670
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: PHP 5.4.45/5.5.29/5.6.13

Timelineinfo

09/03/2015 🔍
09/03/2015 +0 days 🔍
09/08/2015 +5 days 🔍
09/08/2015 +0 days 🔍
09/09/2015 +1 days 🔍
09/14/2015 +5 days 🔍
09/16/2015 +2 days 🔍
09/16/2015 +0 days 🔍
05/16/2016 +243 days 🔍
06/15/2022 +2221 days 🔍

Sourcesinfo

Product: php.org

Advisory: Version 5.6.13
Researcher: Taoguang Chen
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2015-6835 (🔍)
OVAL: 🔍

SecurityTracker: 1033548
Vulnerability Center: 52589 - PHP Remote Code Execution in \x27php_var_unserialize()\x27 Function by Using a Specially Crafted Input, High
SecurityFocus: 76734 - PHP 'php_var_unserialize()' Function Use After Free Remote Code Execution Vulnerability

See also: 🔍

Entryinfo

Created: 09/16/2015 11:27
Updated: 06/15/2022 14:11
Changes: 09/16/2015 11:27 (59), 12/23/2017 13:11 (21), 06/15/2022 14:04 (3), 06/15/2022 14:10 (11), 06/15/2022 14:11 (1)
Complete: 🔍

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