Cisco WebEx Browser Extension up to 1.0.11 on Chrome/Firefox memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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7.9$0-$5k0.00

Summaryinfo

A vulnerability described as critical has been identified in Cisco WebEx Browser Extension up to 1.0.11 on Chrome/Firefox. Affected is an unknown function. Executing a manipulation can lead to memory corruption. This vulnerability is handled as CVE-2017-6753. The attack can be executed remotely. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Cisco WebEx Browser Extension up to 1.0.11 on Chrome/Firefox (Unified Communication Software). It has been declared as critical. This vulnerability affects an unknown code block. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect confidentiality, integrity, and availability.

The bug was discovered 07/17/2017. The weakness was released 07/17/2017 by Tavis Ormandy with Google Project Zero as cisco-sa-20170717-webex as confirmed advisory (Website). The advisory is shared for download at tools.cisco.com. This vulnerability was named CVE-2017-6753 since 03/09/2017. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The advisory points out:

A vulnerability in Cisco WebEx browser extensions for Google Chrome and Mozilla Firefox could allow an unauthenticated, remote attacker to execute arbitrary code with the privileges of the affected browser on an affected system. This vulnerability affects the browser extensions for Cisco WebEx Meetings Server, Cisco WebEx Centers (Meeting Center, Event Center, Training Center, and Support Center), and Cisco WebEx Meetings when they are running on Microsoft Windows.

The vulnerability scanner Nessus provides a plugin with the ID 101816 (Cisco WebEx Extension for Chrome < 1.0.12 'atgpcext' Library GPC Sanitization RCE (cisco-sa-20170717-webex)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Windows and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 370468 (Cisco WebEx Extension Remote Code Execution Vulnerability (cisco-sa-20170717-webex)). The advisory illustrates:

The vulnerability is due to a design defect in the extension. An attacker who can convince an affected user to visit an attacker-controlled web page or follow an attacker-supplied link with an affected browser could exploit the vulnerability. If successful, the attacker could execute arbitrary code with the privileges of the affected browser.

Upgrading to version 1.0.12 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

However, Mac users may use Safari to join WebEx meetings because Safari is not affected by this vulnerability. Windows users may use Internet Explorer and administrators and users of Windows 10 systems may use Microsoft Edge to join and participate in WebEx sessions because Microsoft Internet Explorer and Microsoft Edge are not affected by this vulnerability. Additionally, administrators and users can remove all WebEx software from a Windows system by using the Meeting Services Removal Tool, which is available from https://help.webex.com/docs/DOC-2672.
Attack attempts may be identified with Snort ID 41409.

The vulnerability is also documented in the databases at Tenable (101816), SecurityFocus (BID 99614†) and SecurityTracker (ID 1038911†). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.2
VulDB Meta Temp Score: 8.1

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Cisco): 9.6
Vendor Vector (Cisco): 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Memory corruption
CWE: 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: 101816
Nessus Name: Cisco WebEx Extension for Chrome < 1.0.12 'atgpcext' Library GPC Sanitization RCE (cisco-sa-20170717-webex)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 803167
OpenVAS Name: Cisco WebEx Meetings Server Browser Extension Remote Code Execution Vulnerability
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: WebEx Browser Extension 1.0.12

Snort ID: 41409
Snort Message: POLICY-OTHER Cisco WebEx explicit use of web plugin
Snort Class: 🔍

Timelineinfo

03/09/2017 🔍
07/17/2017 +130 days 🔍
07/17/2017 +0 days 🔍
07/17/2017 +0 days 🔍
07/17/2017 +0 days 🔍
07/17/2017 +0 days 🔍
07/18/2017 +1 days 🔍
07/19/2017 +1 days 🔍
07/25/2017 +6 days 🔍
01/01/2021 +1256 days 🔍

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-20170717-webex
Researcher: Tavis Ormandy
Organization: Google Project Zero
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-6753 (🔍)
GCVE (CVE): GCVE-0-2017-6753
GCVE (VulDB): GCVE-100-103696
SecurityFocus: 99614 - Cisco WebEx Browser Extension CVE-2017-6753 Remote Code Execution Vulnerability
SecurityTracker: 1038911

Entryinfo

Created: 07/18/2017 09:39
Updated: 01/01/2021 17:45
Changes: 07/18/2017 09:39 (94), 10/26/2019 21:00 (6), 01/01/2021 17:45 (3)
Complete: 🔍
Cache ID: 216::103

VulDB is the best source for vulnerability data and more expert information about this specific topic.

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