PHP up to 5.4.44/5.5.28/5.6.12 SplObjectStorage/SplDoublyLinkedList unserialize 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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8.2$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in PHP up to 5.4.44/5.5.28/5.6.12. Affected by this vulnerability is the function unserialize of the component SplObjectStorage/SplDoublyLinkedList. Performing a manipulation results in use after free. This vulnerability is known as CVE-2015-6834. Furthermore, an exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in PHP up to 5.4.44/5.5.28/5.6.12 (Programming Language Software). This affects the function unserialize of the component SplObjectStorage/SplDoublyLinkedList. 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 published 09/03/2015 as Version 5.6.13 as confirmed changelog entry (Website). It is possible to read the advisory at secure.php.net. This vulnerability is uniquely identified as CVE-2015-6834 since 09/08/2015. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details and a public exploit are known.

A public exploit has been developed by SEC Consult and been published 2 years after the advisory. 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 86794 (Debian DLA-341-1 : php5 security update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Debian 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 (40414), Tenable (86794), SecurityFocus (BID 76649†) and SecurityTracker (ID 1033548†). Similar entries are available at VDB-67396, VDB-67398, VDB-67420 and VDB-67631. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
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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
Author: SEC Consult
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 86794
Nessus Name: Debian DLA-341-1 : php5 security update
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: 🔍
Exploit Delay Time: 🔍

Upgrade: PHP 5.4.45/5.5.29/5.6.13

Timelineinfo

08/27/2015 🔍
09/03/2015 +7 days 🔍
09/03/2015 +0 days 🔍
09/08/2015 +5 days 🔍
09/14/2015 +6 days 🔍
09/16/2015 +2 days 🔍
05/16/2016 +243 days 🔍
09/22/2016 +129 days 🔍
09/22/2016 +0 days 🔍
01/04/2025 +3026 days 🔍

Sourcesinfo

Product: php.org

Advisory: Version 5.6.13
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2015-6834 (🔍)
GCVE (CVE): GCVE-0-2015-6834
GCVE (VulDB): GCVE-100-77715

OVAL: 🔍

SecurityFocus: 76649 - PHP CVE-2015-6834 Multiple Remote Code Execution Vulnerabilities
SecurityTracker: 1033548

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

Entryinfo

Created: 09/16/2015 11:27
Updated: 01/04/2025 19:59
Changes: 09/16/2015 11:27 (54), 12/19/2017 08:20 (28), 06/15/2022 14:21 (3), 06/15/2022 14:24 (11), 06/15/2022 14:28 (1), 01/04/2025 19:59 (14)
Complete: 🔍
Cache ID: 216::103

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