What is CVE-2026-21634?

CVE-2026-21634 is a medium-severity vulnerability in Ubiquiti Inc Unifi Protect Application, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 6.5/10. Published 2026-01-05.

How severe is CVE-2026-21634?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Buffer overflow in Ubiquiti Inc Unifi Protect Application

CVE-2026-21634

A malicious actor with access to the adjacent network could overflow the UniFi Protect Application (Version 6.1.79 and earlier) discovery protocol causing it to restart. Affected Products: UniFi Protect Application (Version 6.1.79 an…

Vulnerability class: Buffer Overflow

EPSS: 0.003 (26.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Ubiquiti Inc Unifi Protect Application — versions 6.1.79
Ui Unifi_protect

Weakness classification (CWE)

CWE-119 — Improper Restriction of Operations within the Bounds of a Memory Buffer

References

support@hackerone.com (Vendor Advisory)

Frequently asked questions

What is CVE-2026-21634?: CVE-2026-21634 is a medium-severity vulnerability in Ubiquiti Inc Unifi Protect Application, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 6.5/10. Published 2026-01-05.
How severe is CVE-2026-21634?: Medium severity. CVSS v3 base score is 6.5 out of 10.