CVE-2026-55110 | BDVDB-2026-345231 Detail

UbiquitiUniFi OS Server

Description#

A malicious actor who lures an authenticated user to a malicious page could exploit a Cross-Origin Resource Sharing (CORS) misconfiguration found in UniFi OS to trigger actions in UniFi OS using that user's session.

Impact#

Per CVSS v3.1: confidentiality impact high, integrity impact high, availability impact high. Attack vector: network.

Weaknesses#

CWE-942 Permissive Cross-domain Policy with Untrusted Domains

References#

https://community.ui.com/releases/Security-Advisory-Bulletin-066-066/984eceb3-49c8-4227-942d-671c289b3afc

Exploit#

No public exploit known

History#

Version 12026-07-02Record published in the CVE List.

Published

Published: 2026-07-02
Last modified: 2026-07-02

Vendor information

Vendor: Ubiquiti
Product: UniFi OS Server

All Ubiquiti vulnerabilities

Score

7.5 High

EPSS

less than 1%, Very Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 19.5.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Not classified

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
< 5.1.19
Fixed
5.1.19

Scoring System

CVSS v4.0

Not available

CVSS v3.1

7.5 High

CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H

Metric breakdown
Attack Vector	Network
Attack Complexity	High
Privileges Required	None
User Interaction	Required
Scope	Unchanged
Confidentiality	High
Integrity	High
Availability	High

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).