CVE-2021-21999

VMware Tools for Windows (11.x.y prior to 11.2.6), VMware Remote Console for Windows (12.x prior to 12.0.1) , VMware App Volumes (2.x prior to 2.18.10 and 4 prior to 2103) contain a local privilege escalation vulnerability. An attacker with normal access to a virtual machine may exploit this issue by placing a malicious file renamed as `openssl.cnf' in an unrestricted directory which would allow code to be executed with elevated privileges.

Published: 2021-06-23 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-21999 is rated Moderate Risk (56.5/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.38%). EPSS rose +1.30% over the last day, indicating growing attacker interest. 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-2021-21999

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 0.08% 1.38% +1.30%
2 2025-11-21 0.03% 0.08% +0.04%
3 2025-11-18 — 0.03% —

Full EPSS history (10 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-21999

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/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: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: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]
7.2 2.0 HIGH
AV:L/AC:L/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:L)
Exploitation conditions are straightforward and predictable.
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.
 3.9 10.0 [email protected]

Weakness enumeration for CVE-2021-21999

Affected software / configurations for CVE-2021-21999

Vendor Product Version Raw CPE
vmware app_volumes >= 2.0, < 2.18.10 cpe:2.3:a:vmware:app_volumes:*:*:*:*:*:*:*:*
vmware app_volumes >= 4, < 2103 cpe:2.3:a:vmware:app_volumes:*:*:*:*:*:*:*:*
vmware remote_console >= 12.0.0, < 12.0.1 cpe:2.3:a:vmware:remote_console:*:*:*:*:*:windows:*:*
vmware tools >= 11.0.0, < 11.2.6 cpe:2.3:a:vmware:tools:*:*:*:*:*:windows:*:*

References for CVE-2021-21999

cvelogic Threat Intelligence