CVE-2021-22161

lowpriority · track · 26EPSS 0.005 · 44 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.52% (44th) EPSS

CVSS 3.3 · low

Is it mine?

2 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.3–6.5

v2.03.3lowAV:A/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 6.5 · impact 2.9

v3.16.5mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 3.6

v3.16mediumCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-835USprimary

affected products (2)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
openwrt openwrt19.07.0 → 19.07.6nvdUScpe:2.3:o:openwrt:openwrt:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-02-07modified 2026-06-17

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references (4)

External citations — patches, advisories, analysis.

scry

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