CVE-2021-1536 | Cisco Webex Meetings, Webex Network Recording Player, and Webex Teams DLL Injection Vulnerability

A vulnerability in Cisco Webex Meetings Desktop App for Windows, Cisco Webex Meetings Server, Cisco Webex Network Recording Player for Windows, and Cisco Webex Teams for Windows could allow an authenticated, local attacker to perform a DLL injection attack on an affected device. To exploit this vulnerability, the attacker must have valid credentials on the Windows system. This vulnerability is due to incorrect handling of directory paths at run time. An attacker could exploit this vulnerability by inserting a configuration file in a specific path in the system, which can cause a malicious DLL file to be loaded when the application starts. A successful exploit could allow the attacker to execute arbitrary code on the affected system with the privileges of another user account.

Published: 2021-06-04 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-1536 is rated Low Risk (26.7/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.06%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-1536

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2023-03-07 1.04% 0.06% -0.97%
2 2022-04-01 2.76% 1.04% -1.73%
3 2022-02-04 2.76%

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-1536

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.8 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:L Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
1.3 3.4 [email protected]
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.8 5.9 [email protected]
6.9 2.0 MEDIUM
AV:L/AC:M/Au:N/C:C/I:C/A:C Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
3.4 10.0 [email protected]

Weakness enumeration for CVE-2021-1536

Affected software / configurations for CVE-2021-1536

Vendor Product Version Raw CPE
cisco webex_meetings_desktop cpe:2.3:a:cisco:webex_meetings_desktop:-:*:*:*:*:windows:*:*
cisco webex_meetings_online cpe:2.3:a:cisco:webex_meetings_online:-:*:*:*:*:*:*:*
cisco webex_meetings_server 4.0 cpe:2.3:a:cisco:webex_meetings_server:4.0:*:*:*:*:*:*:*
cisco webex_network_recording_player cpe:2.3:a:cisco:webex_network_recording_player:-:*:*:*:*:windows:*:*
cisco webex_teams 3.0.15485.0 cpe:2.3:a:cisco:webex_teams:3.0.15485.0:*:*:*:*:windows:*:*

References for CVE-2021-1536

cvelogic Threat Intelligence