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Fencer Vulns
high 7.8

CVE-2021-1237 json

Cisco AnyConnect Secure Mobility Client for Windows DLL Injection Vulnerability

published 2021-01-13 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-6704

cvss
7.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 35%
public exploits
0
none known

Summary

A vulnerability in the Network Access Manager and Web Security Agent components of Cisco AnyConnect Secure Mobility Client for Windows could allow an authenticated, local attacker to perform a DLL injection attack. To exploit this vulnerability, the attacker would need to have valid credentials on the Windows system. The vulnerability is due to insufficient validation of resources that are loaded by the application at run time. An attacker could exploit this vulnerability by inserting a configuration file in a specific path in the system which, in turn, causes a malicious DLL file to be loaded when the application starts. A successful exploit could allow the attacker to execute arbitrary code on the affected machine with SYSTEM privileges.

Patch / fix

  • cisco anyconnect_secure_mobility_client 4.9.04043

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
total
Assessed
1 y ago

Exploit prediction

0.41% chance of exploitation in the next 30 days, higher than 35% 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 7.2 AV:L/AC:L/Au:N/C:C/I:C/A:C

Affected products

  • Cisco Cisco AnyConnect Secure Mobility Client

Classification

Weakness
  • CWE-427 Uncontrolled Search Path Element

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.