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 and earlier). Mitigation: Update your UniFi Protect Application to Version 6.2.72 or later.

Vulnerability class: Buffer Overflow

Published · last modified .

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.

EPSS exploit prediction

EPSS: 0.004 (33.9th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 34th percentile — 33.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-21634: held from 0.004 to 0.004.

EPSS over last 30 days · oldest: 0.004 · newest: 0.004 · change: +0.001

Affected products

Weakness classification (CWE)

References

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.