How severe is CVE-2026-21634?

CVE-2026-21634 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2026-21634 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-21634?

CVE-2026-21634 affects Ui Unifi Protect. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-21634?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-21634 have an EU (EUVD) identifier?

Yes. CVE-2026-21634 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-0826.

When was CVE-2026-21634 published?

CVE-2026-21634 was published on 2026-01-05 and last updated on 2026-06-17.

CVE-2026-21634

CVE-2026-21634 is a medium-severity vulnerability in Ui Unifi Protect with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-119.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 0% (27th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-0826
Weakness: CWE-119
Affected product: Ui Unifi Protect
Published: 2026-01-05
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2026-21634?: CVE-2026-21634 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2026-21634 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (27th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-21634?: CVE-2026-21634 affects Ui Unifi Protect. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-21634?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-21634 have an EU (EUVD) identifier?: Yes. CVE-2026-21634 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-0826.
When was CVE-2026-21634 published?: CVE-2026-21634 was published on 2026-01-05 and last updated on 2026-06-17.

References

https://community.ui.com/releases/Security-Advisory-Bulletin-058-058/6922ff20-8cd7-4724-8d8c-676458a2d0f9

Affected products (1)

cpe:2.3:a:ui:unifi_protect:*:*:*:*:*:*:*:*

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