Cisco Webex Teams Client Vulnerability
History:
- 9/10/2020 --- v1.0 -- Initial publication
Summary
On 7th of October 2020, Cisco released three security advisories with an impact evaluated as High [1]. One of them is impacting Windows client version of Cisco Webex Teams [2]. The vulnerability is a DLL Hijacking Vulnerability and could potentially be used by an attacker with a foothold on a system to have another user execute a malicious DLL when Cisco Webex Teams starts.
There is no known attacks leveraging this vulnerability or proof-of-concept available for now.
Technical Details
The vulnerability was assigned CVE-2020-3535 with a CVSS score of 7.8 [3].
There is no technical details available outside of the initial advisory from Cisco. Based on the description, the vulnerability is due to incorrect handling of directory paths at run time -- meaning that an attacker can place a malicious file in a folder with write access for everyone and have the application execute it when starting.
If a high-privileged user of the system starts the application, the attacker can escalate his/her privileges on the system.
Products Affected
This vulnerability affects the following Cisco Webex Teams Client for Windows versions:
- 3.0.13464.0 through 3.0.16040.0
Non-Windows versions are not affected.
Recommendations
CERT-EU recommends updating Cisco Webex Teams Client for Windows to the latest version as soon as possible.
References
[1] https://tools.cisco.com/security/center/publicationListing.x
[3] https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-3535