PHP up to 5.5.34/5.6.20/7.0.5 ext/bcmath/bcmath.c bcpowmod global input validation

CVSS Meta Temp Score
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CTI Interest Score
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9.6$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in PHP up to 5.5.34/5.6.20/7.0.5. This issue affects the function bcpowmod of the file ext/bcmath/bcmath.c. Executing a manipulation of the argument global can lead to input validation. This vulnerability is handled as CVE-2016-4538. The attack can be executed remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in PHP up to 5.5.34/5.6.20/7.0.5 (Programming Language Software). It has been declared as critical. This vulnerability affects the function bcpowmod of the file ext/bcmath/bcmath.c. The manipulation of the argument global with an unknown input leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

The bcpowmod function in ext/bcmath/bcmath.c in PHP before 5.5.35, 5.6.x before 5.6.21, and 7.x before 7.0.6 modifies certain data structures without considering whether they are copies of the _zero_, _one_, or _two_ global variable, which allows remote attackers to cause a denial of service or possibly have unspecified other impact via a crafted call.

The weakness was released 05/22/2016 (Website). The advisory is available at php.net. This vulnerability was named CVE-2016-4538 since 05/05/2016. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 91320 (Ubuntu 12.04 LTS / 14.04 LTS / 15.10 / 16.04 LTS : php5, php7.0 vulnerabilities (USN-2984-1)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Ubuntu Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 11623 (PHP Versions Prior to 5.6.21/5.5.35 Multiple Vulnerabilities).

Upgrading to version 5.5.35, 5.6.21 or 7.0.6 eliminates this vulnerability. A possible mitigation has been published 2 days after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (91320) and SecurityFocus (BID 90173†). Entries connected to this vulnerability are available at VDB-67396, VDB-67398, VDB-67420 and VDB-67724. If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.8
VulDB Meta Temp Score: 9.6

VulDB Base Score: 9.8
VulDB Temp Score: 9.4
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: Input validation
CWE: CWE-20
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: 91320
Nessus Name: Ubuntu 12.04 LTS / 14.04 LTS / 15.10 / 16.04 LTS : php5, php7.0 vulnerabilities (USN-2984-1)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 63997
OpenVAS Name: Ubuntu Update for php7.0 USN-2984-1
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
Exposure Time: 🔍

Upgrade: PHP 5.5.35/5.6.21/7.0.6
Patch: d650063a0457aec56364e4005a636dc6c401f9cd

Timelineinfo

05/05/2016 🔍
05/05/2016 +0 days 🔍
05/21/2016 +16 days 🔍
05/22/2016 +1 days 🔍
05/23/2016 +1 days 🔍
05/24/2016 +1 days 🔍
05/25/2016 +1 days 🔍
08/21/2022 +2279 days 🔍

Sourcesinfo

Product: php.org

Advisory: 72093
Status: Not defined
Confirmation: 🔍

CVE: CVE-2016-4538 (🔍)
GCVE (CVE): GCVE-0-2016-4538
GCVE (VulDB): GCVE-100-87586

OVAL: 🔍

SecurityFocus: 90173 - PHP 'bcmath.c' Multiple Local Heap Overflow Vulnerabilities

See also: 🔍

Entryinfo

Created: 05/23/2016 10:33
Updated: 08/21/2022 15:46
Changes: 05/23/2016 10:33 (69), 12/10/2018 08:16 (13), 08/21/2022 15:39 (6), 08/21/2022 15:46 (1)
Complete: 🔍
Cache ID: 216::103

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