PHP 7.x Unserialization 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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A vulnerability, which was classified as critical, has been found in PHP 7.x (Programming Language Software). This issue affects some unknown functionality of the component Unserialization. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

In all versions of PHP 7, during the unserialization process, resizing the 'properties' hash table of a serialized object may lead to use-after-free. A remote attacker may exploit this bug to gain arbitrary code execution.

The bug was discovered 12/27/2016. The weakness was published 01/12/2017 with CheckPoint (Website). It is possible to read the advisory at The identification of this vulnerability is CVE-2016-7479 since 09/09/2016. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. The technical details are unknown and an exploit is not publicly available.

The vulnerability was handled as a non-public zero-day exploit for at least 15 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 96800 (PHP 7.0.x < 7.0.15 Multiple Vulnerabilities), which helps to determine the existence of the flaw in a target environment. It is assigned to the family CGI abuses and running in the context r. The commercial vulnerability scanner Qualys is able to test this issue with plugin 196693 (Ubuntu Security Notification for Php5 Vulnerabilities (USN-3196-1)).

Upgrading eliminates this vulnerability. A possible mitigation has been published 1 weeks after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (96800). Similar entries are available at 95027, 95169, 95170 and 95171.






CPE 2.3info

CPE 2.2info


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

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
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NVD Base Score: 9.8
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Class: Use after free
CWE: CWE-416 / CWE-119
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

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Nessus ID: 96800
Nessus Name: PHP 7.0.x < 7.0.15 Multiple Vulnerabilities
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OpenVAS ID: 850584
OpenVAS Name: SuSE Update for php7 openSUSE-SU-2017:0588-1 (php7)
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Threat Intelligenceinfo

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Recommended: Upgrade
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09/09/2016 🔍
12/27/2016 +109 days 🔍
12/29/2016 +2 days 🔍
01/11/2017 +13 days 🔍
01/12/2017 +1 days 🔍
01/12/2017 +0 days 🔍
01/19/2017 +7 days 🔍
01/26/2017 +7 days 🔍
10/28/2022 +2101 days 🔍



Advisory: RHSA-2018:1296
Organization: CheckPoint
Status: Not defined
Confirmation: 🔍

CVE: CVE-2016-7479 (🔍)
SecurityTracker: 1037659
SecurityFocus: 95151 - PHP CVE-2016-7479 Denial of Service Vulnerability
OSVDB: - CVE-2016-7479 - PHP - Use-After-Free Issue

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Created: 01/12/2017 10:31 AM
Updated: 10/28/2022 12:18 PM
Changes: 01/12/2017 10:31 AM (74), 07/20/2020 11:09 AM (9), 10/28/2022 12:18 PM (4)
Complete: 🔍


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