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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CTI Interest Score
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8.2$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in PHP up to 5.4.44/5.5.28/5.6.12. Impacted is an unknown function of the component Session Deserializer. Performing a manipulation results in use after free. This vulnerability is cataloged as CVE-2015-6835. Furthermore, there is an exploit available. You should upgrade the affected component.

Detailsinfo

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. Technical details are unknown but a public exploit is available.

The exploit is shared for download at exploit-db.com. It is declared as proof-of-concept. We expect the 0-day to have been worth approximately $5k-$25k. 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 databases at Exploit-DB (38123), Tenable (86654), SecurityFocus (BID 76734†), SecurityTracker (ID 1033548†) and Vulnerability Center (SBV-52589†). The entries VDB-67396, VDB-67398, VDB-67420 and VDB-67724 are related to this item. If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.2

VulDB Base Score: 7.3
VulDB Temp Score: 6.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

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

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

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: 🔍

Exploit-DB: 🔍

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 🔍
01/05/2025 +3156 days 🔍

Sourcesinfo

Product: php.org

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

CVE: CVE-2015-6835 (🔍)
GCVE (CVE): GCVE-0-2015-6835
GCVE (VulDB): GCVE-100-77709

OVAL: 🔍

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

scip Labs: https://www.scip.ch/en/?labs.20161013
See also: 🔍

Entryinfo

Created: 09/16/2015 11:27
Updated: 01/05/2025 06:43
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), 01/05/2025 06:43 (23)
Complete: 🔍
Cache ID: 216:A8A:103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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