How severe is CVE-2021-1568?

CVE-2021-1568 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-1568 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-1568?

CVE-2021-1568 affects Cisco Anyconnect Secure Mobility Client. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-1568?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-1568 published?

CVE-2021-1568 was published on 2021-06-16 and last updated on 2026-06-17.

CVE-2021-1568

CVE-2021-1568 is a medium-severity vulnerability in Cisco Anyconnect Secure Mobility Client with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-789.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 2.1
EPSS exploit prediction: 0% (11th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-789
Affected product: Cisco Anyconnect Secure Mobility Client
Published: 2021-06-16
Last modified: 2026-06-17

Description

A vulnerability in Cisco AnyConnect Secure Mobility Client for Windows could allow an authenticated, local attacker to cause a denial of service (DoS) condition on an affected system. This vulnerability is due to uncontrolled memory allocation. An attacker could exploit this vulnerability by copying a crafted file to a specific folder on the system. A successful exploit could allow the attacker to crash the VPN Agent service when the affected application is launched, causing it to be unavailable to all users of the system. To exploit this vulnerability, the attacker must have valid credentials on a multiuser Windows system.

Frequently asked questions

What is CVE-2021-1568?: A vulnerability in Cisco AnyConnect Secure Mobility Client for Windows could allow an authenticated, local attacker to cause a denial of service (DoS) condition on an affected system. This vulnerability is due to uncontrolled memory allocation. An attacker could exploit this vulnerability by copying a crafted file to a specific folder on the system. A successful exploit could allow the attacker to crash the VPN Agent service when the affected application is launched, causing it to be unavailable to all users of the system. To exploit this vulnerability, the attacker must have valid credentials on a multiuser Windows system.
How severe is CVE-2021-1568?: CVE-2021-1568 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-1568 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (11th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1568?: CVE-2021-1568 affects Cisco Anyconnect Secure Mobility Client. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-1568?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-1568 published?: CVE-2021-1568 was published on 2021-06-16 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-anyconnect-dos-hMhyDfb8

Affected products (1)

cpe:2.3:a:cisco:anyconnect_secure_mobility_client:*:*:*:*:*:windows:*:*

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