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

CVSS Meta Temp Score
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CTI Interest Score
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7.4$0-$5k0.00

Summaryinfo

A vulnerability identified as problematic has been detected in PHP up to 7.0.13. Affected by this issue is some unknown functionality of the file ext/standard/var.c of the component Unserialization. This manipulation causes use after free. This vulnerability is handled as CVE-2016-9936. The attack can be initiated remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

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 summary by CVE is:

The unserialize implementation in ext/standard/var.c in PHP 7.x before 7.0.14 allows remote attackers to cause a denial of service (use-after-free) or possibly have unspecified other impact via crafted serialized data. NOTE: this vulnerability exists because of an incomplete fix for CVE-2015-6834.

The bug was discovered 12/12/2016. The weakness was released 01/04/2017 (Website). The advisory is shared at lists.opensuse.org. 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 databases at Tenable (96806) and SecurityFocus (BID 94849†). Entries connected to this vulnerability are available at VDB-80329, VDB-91502, VDB-91503 and VDB-95170. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
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: 🔍

CVSSv2info

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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: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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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: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: PHP 7.0.14
Patch: github.com

Timelineinfo

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 🔍

Sourcesinfo

Product: php.org

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

CVE: CVE-2016-9936 (🔍)
GCVE (CVE): GCVE-0-2016-9936
GCVE (VulDB): GCVE-100-95041
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: 🔍

Entryinfo

Created: 01/05/2017 12:57
Updated: 10/27/2022 16:14
Changes: 01/05/2017 12:57 (82), 07/14/2020 17:53 (1), 10/27/2022 16:14 (5)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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