CVE-2021-1366 json
Cisco AnyConnect Secure Mobility Client for Windows with VPN Posture (HostScan) Module DLL Hijacking Vulnerability
published 2021-02-17 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-6833
- cvss
- 7.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.3%
- EPSS 1.3% chance of exploitation in 30 days, percentile 69%
- public exploits
- 0
- none known
Summary
A vulnerability in the interprocess communication (IPC) channel of Cisco AnyConnect Secure Mobility Client for Windows could allow an authenticated, local attacker to perform a DLL hijacking attack on an affected device if the VPN Posture (HostScan) Module is installed on the AnyConnect client. This vulnerability is due to insufficient validation of resources that are loaded by the application at run time. An attacker could exploit this vulnerability by sending a crafted IPC message to the AnyConnect process. A successful exploit could allow the attacker to execute arbitrary code on the affected machine with SYSTEM privileges. To exploit this vulnerability, the attacker needs valid credentials on the Windows system.
Patch / fix
- cisco anyconnect_secure_mobility_client 4.9.05042
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 2 y ago
Exploit prediction
1.25% chance of exploitation in the next 30 days, higher than 69% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| 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 | 6.9 | AV:L/AC:M/Au:N/C:C/I:C/A:C |
Affected products
- Cisco Cisco AnyConnect Secure Mobility Client
Classification
References
Sources
- CVE List CVE-2021-1366
- NVD CVE-2021-1366
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