CVE-2021-22161

Description

In OpenWrt 19.07.x before 19.07.7, when IPv6 is used, a routing loop can occur that generates excessive network traffic between an affected device and its upstream ISP's router. This occurs when a link prefix route points to a point-to-point link, a destination IPv6 address belongs to the prefix and is not a local IPv6 address, and a router advertisement is received with at least one global unique IPv6 prefix for which the on-link flag is set. This affects the netifd and odhcp6c packages.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.11%
Vendor Advisory openwrt.org
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://openwrt.org/advisory/2021-02-02-1 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-22161?
CVE-2021-22161 has been scored as a medium severity vulnerability.
How to fix CVE-2021-22161?
To fix CVE-2021-22161, 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-2021-22161 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-22161 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.
This platform uses data from the NIST NVD, MITRE CVE, MITRE CWE, First.org and CISA KEV but is not endorsed or certified by these entities. CVE is a registred trademark of the MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. CWE is a registred trademark of the MITRE Corporation and the authoritative source of CWE content is MITRE's CWE web site.
© 2025 Under My Watch. All Rights Reserved.