CVE-2026-55110

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.

Published: 2026-07-02 Last update: 2026-07-09 Assigner: [email protected] Source: [email protected]
NVD Status：Undergoing Analysis，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-55110 is rated Low Risk (31.3/100): CVSS High severity, with low exploitation likelihood (EPSS 0.14%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-55110

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-07-10 0.18% 0.14% -0.04%
2 2026-07-03 — 0.18% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-55110

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.6 5.9 [email protected]
6.1 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 2.7 [email protected]

Weakness enumeration for CVE-2026-55110

GitHub Security Advisory for CVE-2026-55110

GHSA-fwmw-87x4-wjv5 · Severity: high — A malicious actor who lures an authenticated user to a malicious page could exploit a Cross...

Affected software / configurations for CVE-2026-55110

Vendor Product Version Raw CPE
ui unifi_os_server <= 5.1.15 cpe:2.3:a:ui:unifi_os_server:*:*:*:*:*:*:*:*
ui unifi_dream_machine_beast_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_dream_machine_beast_firmware:*:*:*:*:*:*:*:*
ui unifi_dream_machine_pro_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_dream_machine_pro_firmware:*:*:*:*:*:*:*:*
ui unifi_dream_machine_special_edition_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_dream_machine_special_edition_firmware:*:*:*:*:*:*:*:*
ui unifi_dream_machine_pro_max_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_dream_machine_pro_max_firmware:*:*:*:*:*:*:*:*
ui enterprise_fortress_gateway_firmware <= 5.1.15 cpe:2.3:o:ui:enterprise_fortress_gateway_firmware:*:*:*:*:*:*:*:*
ui unifi_dream_router_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_dream_router_firmware:*:*:*:*:*:*:*:*
ui unifi_dream_wall_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_dream_wall_firmware:*:*:*:*:*:*:*:*
ui unifi_dream_router_7_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_dream_router_7_firmware:*:*:*:*:*:*:*:*
ui unifi_express_7_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_express_7_firmware:*:*:*:*:*:*:*:*
ui unifi_cloudkey_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_cloudkey_firmware:*:*:*:*:*:*:*:*
ui unifi_cloud_key_plus_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_cloud_key_plus_firmware:*:*:*:*:*:*:*:*
ui unifi_cloudkey_enterprise_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_cloudkey_enterprise_firmware:*:*:*:*:*:*:*:*
ui unifi_network_video_recorder_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_network_video_recorder_firmware:*:*:*:*:*:*:*:*
ui unifi_network_video_recorder_pro_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_network_video_recorder_pro_firmware:*:*:*:*:*:*:*:*
ui unifi_network_video_recorder_instant_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_network_video_recorder_instant_firmware:*:*:*:*:*:*:*:*
ui enterprise_network_video_recorder_firmware <= 5.1.15 cpe:2.3:o:ui:enterprise_network_video_recorder_firmware:*:*:*:*:*:*:*:*
ui enterprise_network_video_recorder_core_firmware <= 5.1.15 cpe:2.3:o:ui:enterprise_network_video_recorder_core_firmware:*:*:*:*:*:*:*:*
ui unifi_network_video_recorder_g2_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_network_video_recorder_g2_firmware:*:*:*:*:*:*:*:*
ui unifi_network_video_recorder_g2_pro_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_network_video_recorder_g2_pro_firmware:*:*:*:*:*:*:*:*
ui unifi_cloud_gateway_ultra_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_cloud_gateway_ultra_firmware:*:*:*:*:*:*:*:*
ui unifi_cloud_gateway_max_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_cloud_gateway_max_firmware:*:*:*:*:*:*:*:*
ui unifi_cloud_gateway_industrial_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_cloud_gateway_industrial_firmware:*:*:*:*:*:*:*:*
ui unifi_cloud_gateway_fiber_firmware <= 5.1.15 cpe:2.3:o:ui:unifi_cloud_gateway_fiber_firmware:*:*:*:*:*:*:*:*
ui unas_2_firmware <= 5.1.16 cpe:2.3:o:ui:unas_2_firmware:*:*:*:*:*:*:*:*
ui unas_4_firmware <= 5.1.16 cpe:2.3:o:ui:unas_4_firmware:*:*:*:*:*:*:*:*
ui unas_pro_firmware <= 5.1.16 cpe:2.3:o:ui:unas_pro_firmware:*:*:*:*:*:*:*:*
ui unas_pro_4_firmware <= 5.1.16 cpe:2.3:o:ui:unas_pro_4_firmware:*:*:*:*:*:*:*:*
ui unas_pro_8_firmware <= 5.1.16 cpe:2.3:o:ui:unas_pro_8_firmware:*:*:*:*:*:*:*:*
ui enterprise_firewall_core_firmware <= 5.1.18 cpe:2.3:o:ui:enterprise_firewall_core_firmware:*:*:*:*:*:*:*:*

References for CVE-2026-55110

cvelogic Threat Intelligence