Cisco AnyConnect Secure Mobility Client Denial of Service Vulnerability

published 2021-02-24 5y ago modified 2026-06-17 4mo ago also EUVD-2021-6917

cvss: 5.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 14%
public exploits: 0; none known

A vulnerability in the interprocess communication (IPC) channel of Cisco AnyConnect Secure Mobility Client could allow an authenticated, local attacker to cause a denial of service (DoS) condition on an affected device. To exploit this vulnerability, the attacker would need to have valid credentials on the device. The vulnerability is due to insufficient validation of user-supplied input. An attacker could exploit this vulnerability by sending one or more crafted IPC messages to the AnyConnect process on an affected device. A successful exploit could allow the attacker to stop the AnyConnect process, causing a DoS condition on the device. Note: The process under attack will automatically restart so no action is needed by the user or admin.

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CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 2y ago (2024-11-08)

Exploit prediction

0.23% chance of exploitation in the next 30 days, higher than 14% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.5	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD	3.1	5.5	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	4.9	AV:L/AC:L/Au:N/C:N/I:N/A:C

Affected products

Cisco Cisco AnyConnect Secure Mobility Client

Classification

Weakness

CWE-20 Improper Input Validation

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-anyconnect-dos-55AYyxYr
vendor-advisory

Sources

CVE List CVE-2021-1450
NVD CVE-2021-1450

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