CVE-2020-3126 | Cisco Webex Meetings Multimedia Viewer Vulnerability

vulnerability within the Multimedia Viewer feature of Cisco Webex Meetings could allow an authenticated, remote attacker to bypass security protections. The vulnerability is due to missing security warning dialog boxes when a room host views shared multimedia files. An authenticated, remote attacker could exploit this vulnerability by using the host role to share files within the Multimedia sharing feature and convincing a former room host to view that file. A warning dialog normally appears cautioning users before the file is displayed; however, the former host would not see that warning dialog, and any shared multimedia would be rendered within the user's browser. The attacker could leverage this behavior to conduct additional attacks by including malicious files within a targeted room host's browser window.

Published: 2020-04-13 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-3126 is rated Low Risk (31.5/100): CVSS Low severity, with medium exploitation likelihood (EPSS 0.86%). 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-2020-3126

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 2026-06-15 0.10% 0.86% +0.76%
2 2025-11-21 0.15% 0.10% -0.05%
3 2025-11-18 — 0.15% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-3126

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
3.0 3.1 LOW
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 1.3 1.4 [email protected]
3.5 3.1 LOW
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
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:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.1 1.4 [email protected]
3.5 2.0 LOW
AV:N/AC:M/Au:S/C:N/I:P/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:N)
No availability impact.
 6.8 2.9 [email protected]

Weakness enumeration for CVE-2020-3126

Affected software / configurations for CVE-2020-3126

Vendor Product Version Raw CPE
cisco webex_meetings_server t39.3 cpe:2.3:a:cisco:webex_meetings_server:t39.3:*:*:*:*:*:*:*

References for CVE-2020-3126

cvelogic Threat Intelligence