PT-2021-14880 · Netifd+2 · Netifd+2

Xiang Li · Published 2021-02-07 · Updated 2023-05-24 · CVE-2021-22161

Positive Technologies (AI Summary)

CVSS v3.1

6.5

Medium

Base vector

AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions: OpenWrt versions 19.07.x through 19.07.6

Description: A routing loop can occur when IPv6 is used, generating excessive network traffic between an affected device and its upstream ISP's router. This happens 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. The netifd and odhcp6c packages are affected.

Recommendations: For OpenWrt versions 19.07.x through 19.07.6, update to version 19.07.7 or later to resolve the issue. As a temporary workaround, consider disabling IPv6 until a patch is available. Restrict access to the netifd and odhcp6c packages to minimize the risk of exploitation. Avoid using IPv6 prefix routes that point to point-to-point links until the issue is resolved.

Fix

Infinite Loop

Weakness Enumeration

CWE-835

Related Identifiers

CVE-2021-22161

Affected Products

Openwrt

Netifd

Odhcp6C

References · 7

• https://nvd.nist.gov/vuln/detail/CVE-2021-22161 · Security Note
• https://openwrt.org/advisory/2021-02-02-1 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2021-22161 · Vendor Advisory
• https://t.me/cvenotify/51048 · Telegram Post
• https://t.me/cvenotify/9553 · Telegram Post
• https://t.me/cvenotify/9555 · Telegram Post
• https://t.me/cvenotify/9798 · Telegram Post