What is CVE-2021-30072?

CVE-2021-30072 is a critical-severity vulnerability in Dlink Dir-878, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2021-04-02.

How severe is CVE-2021-30072?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Buffer overflow in Dlink Dir-878

CVE-2021-30072

An issue was discovered in prog.cgi on D-Link DIR-878 1.30B08 devices. Because strcat is misused, there is a stack-based buffer overflow that does not require authentication.

Vulnerability class: Buffer Overflow

Published 2021-04-02 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.014 (72.0th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 72nd percentile — 72.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.014 · newest: 0.014 · change: 0.000

Affected products

Dlink Dir-878 — versions ax
Dlink Dir-878 Firmware

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

www.dlink.com/en/security-bulletin/ (Vendor Advisory)
supportannouncement.us.dlink.com/announcement/publication.aspx (Vendor Advisory)

Frequently asked questions

What is CVE-2021-30072?: CVE-2021-30072 is a critical-severity vulnerability in Dlink Dir-878, classified under Out-of-bounds Write. CVSS score: 9.8/10. Published 2021-04-02.
How severe is CVE-2021-30072?: Critical severity. CVSS v3 base score is 9.8 out of 10.