What is CVE-2021-28961?

CVE-2021-28961 is a high-severity vulnerability in Openwrt, classified under OS Command Injection. CVSS score: 8.8/10. Published 2021-03-21.

How severe is CVE-2021-28961?

High severity. CVSS v3 base score is 8.8 out of 10.

RCE in Openwrt

CVE-2021-28961

applications/luci-app-ddns/luasrc/model/cbi/ddns/detail.lua in the DDNS package for OpenWrt 19.07 allows remote authenticated users to inject arbitrary commands via POST requests.

Vulnerability class: Command Injection (OS Command Injection)

Published 2021-03-21 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.015 (73.9th percentile), scored 2026-10-07.

Low probability of exploitation in the next 30 days, but still tracked. 74th percentile — 73.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.015 · newest: 0.015 · change: 0.000

Affected products

Openwrt — versions 19.07.0

Weakness classification (CWE)

CWE-78 — OS Command Injection

References

github.com/openwrt/luci/commit/9df7ea4d66644df69fcea18b36bc465912ffc (Patch, Third Party Advisory)
openwrt.org/advisory/2021-08-01-3 (Patch, Vendor Advisory)

Frequently asked questions

What is CVE-2021-28961?: CVE-2021-28961 is a high-severity vulnerability in Openwrt, classified under OS Command Injection. CVSS score: 8.8/10. Published 2021-03-21.
How severe is CVE-2021-28961?: High severity. CVSS v3 base score is 8.8 out of 10.