CVE-2021-44466

Bitmask Riseup VPN 0.21.6 contains a local privilege escalation flaw due to improper access controls. When the software is installed with a non-default installation directory off of the system root, the installer fails to properly set ACLs. This allows lower privileged users to replace the VPN executable with a malicious one. When a higher privileged user such as an Administrator launches that executable, it is possible for the lower privileged user to escalate to Administrator privileges.

Published: 2021-12-30 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-44466 is rated Moderate Risk (40.4/100): CVSS High severity, with low exploitation likelihood (EPSS 0.40%). 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-2021-44466

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 0.15% 0.40% +0.25%
2 2025-06-25 0.12% 0.15% +0.03%
3 2025-03-17 0.12%

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-44466

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.3 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:L/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: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: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.
1.3 5.9 [email protected]
4.6 2.0 MEDIUM
AV:N/AC:H/Au:S/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:H)
Exploitation requires uncommon or highly specific conditions.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
3.9 6.4 [email protected]

Weakness enumeration for CVE-2021-44466

Affected software / configurations for CVE-2021-44466

Vendor Product Version Raw CPE
leap bitmask_riseup_vpn 0.21.6 cpe:2.3:a:leap:bitmask_riseup_vpn:0.21.6:*:*:*:*:*:*:*

References for CVE-2021-44466

URL Tags
https://www.tenable.com/security/research/tra-2021-58 Patch Third Party Advisory
cvelogic Threat Intelligence