CVE-2020-3427 json
Duo Authentication for Windows Logon and RDP Privilege Escalation Vulnerability
published 2020-10-14 6 y ago modified 2026-06-17 4 mo ago also EUVD-2020-24698
- cvss
- 6.6
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 23%
- public exploits
- 0
- none known
Summary
The Windows Logon installer prior to 4.1.2 did not properly validate file installation paths. This allows an attacker with local user privileges to coerce the installer to write to arbitrary privileged directories. If successful, an attacker can manipulate files used by Windows Logon, cause Denial of Service (DoS) by deleting file(s), or replace system files to potentially achieve elevation of privileges. Note that this can only exploitable during new installations while the installer is running and is not exploitable once installation is finished. Versions 4.1.2 of Windows Logon addresses this issue.
Patch / fix
- Cisco Duo Authentication for Windows Logon and RDP 4.1.2
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 23 mo ago
Exploit prediction
0.31% chance of exploitation in the next 30 days, higher than 23% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.6 | CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N |
| NVD | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 4.6 | AV:L/AC:L/Au:N/C:P/I:P/A:P |
Affected products
- Cisco Duo Authentication for Windows Logon and RDP
Classification
- Weakness
-
- CWE-280 Improper Handling of Insufficient Permissions or Privileges
References
-
duo.com
/docs/rdp-notes
vendor-advisory, release-notes
Sources
- CVE List CVE-2020-3427
- NVD CVE-2020-3427
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