CVE-2020-3998

VMware Horizon Client for Windows (5.x prior to 5.5.0) contains an information disclosure vulnerability. A malicious attacker with local privileges on the machine where Horizon Client for Windows is installed may be able to retrieve hashed credentials if the client crashes.

Published: 2020-10-23 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2020-3998 is rated Moderate Risk (41.2/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.24%). Mandatory action: Review affected assets and schedule remediation.

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-2020-3998

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 2025-03-30 0.46% 0.24% -0.23%
2 2025-03-29 0.21% 0.46% +0.26%
3 2025-03-17 0.21%

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-3998

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/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:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
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:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
2.8 3.6 [email protected]
4.0 2.0 MEDIUM
AV:N/AC:L/Au:S/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
8.0 2.9 [email protected]

Weakness enumeration for CVE-2020-3998

Affected software / configurations for CVE-2020-3998

Vendor Product Version Raw CPE
vmware horizon_client >= 5.0.0, < 5.5.0 cpe:2.3:a:vmware:horizon_client:*:*:*:*:*:*:*:*

References for CVE-2020-3998

cvelogic Threat Intelligence