PHP up to 7.0.13 Unserialization ext/standard/var.c use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.

A vulnerability classified as problematic was found in PHP up to 7.0.13 (Programming Language Software). Affected by this vulnerability is some unknown functionality of the file ext/standard/var.c of the component Unserialization. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect availability.

The bug was discovered 12/12/2016. The weakness was released 01/04/2017 (Website). The advisory is shared at This vulnerability is known as CVE-2016-9936 since 12/12/2016. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 23 days. During that time the estimated underground price was around $5k-$25k. The vulnerability scanner Nessus provides a plugin with the ID 96806 (Amazon Linux AMI : php70 (ALAS-2017-788)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Amazon Linux Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 169472 (SUSE Enterprise Linux Security Update for php7 (SUSE-SU-2017:0017-1)).

Upgrading to version 7.0.14 eliminates this vulnerability. A possible mitigation has been published 4 weeks after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (96806). Entries connected to this vulnerability are available at 80329, 91502, 91503 and 95170.





  • open-source

CPE 2.3info

CPE 2.2info


VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.4

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍



VulDB Base Score: 🔍
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NVD Base Score: 🔍


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: 🔍


Nessus ID: 96806
Nessus Name: Amazon Linux AMI : php70 (ALAS-2017-788)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 841810
OpenVAS Name: Ubuntu Update for php7.0 USN-3211-2
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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


Recommended: Upgrade
Status: 🔍

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

Upgrade: PHP 7.0.14


12/12/2016 🔍
12/12/2016 +0 days 🔍
12/12/2016 +0 days 🔍
01/04/2017 +23 days 🔍
01/04/2017 +0 days 🔍
01/05/2017 +1 days 🔍
01/26/2017 +21 days 🔍
01/27/2017 +1 days 🔍
10/27/2022 +2099 days 🔍



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

CVE: CVE-2016-9936 (🔍)
SecurityFocus: 94849 - PHP 'ext/standard/var.c' Incomplete Fix Use After Free Remote Code Execution Vulnerability
OSVDB: - CVE-2016-9936 - PHP - Use-After-Free Issue

See also: 🔍


Created: 01/05/2017 12:57 PM
Updated: 10/27/2022 04:14 PM
Changes: 01/05/2017 12:57 PM (82), 07/14/2020 05:53 PM (1), 10/27/2022 04:14 PM (5)
Complete: 🔍


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