CVE detail

CVE-2021-1620 — CVE-2021-1620

Published 2021-09-23 · Modified 2026-06-17 · Vendor cisco · Product ios · Source nvd
HIGH
severity
CVSS-derived band
7.7
CVSS v3
0–10 scale
0.0107
EPSS probability
exploitation probability, 30d
62.0%
EPSS percentile
percentile vs all CVEs
NOT LISTED
CISA KEV
known exploited catalog

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.

Remediation

ProductVulnerable rangeFixed versionAdvisory
Cisco Cisco IOSnot specifiedadvisory ↗

References

cvedb.io · NVD · CISA KEV · FIRST EPSS · vendor advisories (CVE Program List v5). Informational only, no warranty — verify every remediation against the vendor advisory before acting on it. This product uses data from the NVD API but is not endorsed or certified by the NVD, CISA, FIRST.org or any vendor named. CVE® is a registered trademark of The MITRE Corporation.