CVE-2021-1620

Cisco IOS and IOS XE Software IKEv2 AutoReconnect Feature Denial of Service Vulnerability

Description

A vulnerability in the Internet Key Exchange Version 2 (IKEv2) support for the AutoReconnect feature of Cisco IOS Software and Cisco IOS XE Software could allow an authenticated, remote attacker to exhaust the free IP addresses from the assigned local pool. This vulnerability occurs because the code does not release the allocated IP address under certain failure conditions. An attacker could exploit this vulnerability by trying to connect to the device with a non-AnyConnect client. A successful exploit could allow the attacker to exhaust the IP addresses from the assigned local pool, which prevents users from logging in and leads to a denial of service (DoS) condition.

Categories

7.7
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.33%
Vendor Advisory cisco.com
Affected: Cisco Cisco IOS
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-1620?
CVE-2021-1620 has been scored as a high severity vulnerability.
How to fix CVE-2021-1620?
To fix CVE-2021-1620, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-1620 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-1620 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-1620?
CVE-2021-1620 affects Cisco Cisco IOS.
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