Ubiquiti UniFi OS Server: Server-Side Request Forgery (SSRF) (CVE-2026-54401)
Published Last modified Sources: BSI, CVE.org
What is affected, what to do
A malicious actor with access to the network and low privileges could exploit a Server-Side Request Forgery (SSRF) to escalate privileges within such UniFi OS devices or instances.
Update Ubiquiti UniFi OS Server to version 5.1.19, Ubiquiti Dream Machines to version 5.1.19, Ubiquiti Enterprise Fortress Gateway to version 5.1.19.
- Affected
- Ubiquiti UniFi OS Server
lt *..5.1.19 - Ubiquiti Dream Machines
lt *..5.1.19 - Ubiquiti Enterprise Fortress Gateway
lt *..5.1.19 - Ubiquiti Dream Wall
lt *..5.1.19 - Ubiquiti Dream Routers
lt *..5.1.19 - Ubiquiti Express 7
lt *..5.1.19 - Ubiquiti Cloud Keys
lt *..5.1.19 - Ubiquiti Network Video Recorders
lt *..5.1.19 - Ubiquiti Enterprise Video Recorders
lt *..5.1.19 - Ubiquiti Cloud Gateways
lt *..5.1.19 - Ubiquiti Network Attached Storage
lt *..5.1.19 - Ubiquiti Enterprise Firewall Core
lt *..5.1.19
- Ubiquiti UniFi OS Server
- Fixed in
- Ubiquiti UniFi OS Server
5.1.19 - Ubiquiti Dream Machines
5.1.19 - Ubiquiti Enterprise Fortress Gateway
5.1.19 - Ubiquiti Dream Wall
5.1.19 - Ubiquiti Dream Routers
5.1.19 - Ubiquiti Express 7
5.1.19 - Ubiquiti Cloud Keys
5.1.19 - Ubiquiti Network Video Recorders
5.1.19 - Ubiquiti Enterprise Video Recorders
5.1.19 - Ubiquiti Cloud Gateways
5.1.19 - Ubiquiti Network Attached Storage
5.1.19 - Ubiquiti Enterprise Firewall Core
5.1.19
- Ubiquiti UniFi OS Server
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Metrics
8.8
Priority
XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.
Source: NVD, CVSS v3
7.7
CVSS v3
Severity High on the scale from 0 to 10.
Source: BSI, CVE.org
0.4 %
EPSS score
Low — model estimates < 1% exploitation likelihood.
Source: FIRST EPSS, percentile 37.3
Show all metrics
- Severity
- High
Priority (0–325)
The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?
Read in glossary- 69.41 Methodology
Exploit maturity
An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.
Read in glossary- no public PoC known
XIEM Effective CVSS
XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.
Read in glossary- 8.8 Methodology
CVSS v3
CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.
Read in glossary- 7.7
EPSS score
The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.
Read in glossary- 0.4 %
- Low — model estimates < 1% exploitation likelihood.
EPSS percentile
The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.
Read in glossary- 37.3
- High — this CVE ranks above the median of all CVEs scored today (rank ≥ 36%).
KEV status
The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.
Read in glossary- —
- Published
- CISA assessment (SSVC)
- Exploitation: none known · not automatable · Technical impact: partial
- Source: CISA Vulnrichment, as of 2 July 2026
CWE
CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.
Read in glossary- CWE-918
Detection rules
No NEOSEC detection rule is available for this vulnerability yet.
Classification under NIS2 and CRA
Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.
NIS2
NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.
Read in glossary- High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
CRA
The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.
Read in glossary- From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001
ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.
Read in glossary- Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.
Description
A malicious actor with access to the network and low privileges could exploit a Server-Side Request Forgery (SSRF) to escalate privileges within such UniFi OS devices or instances.
Source: BSI WID Portal, BSI CSAF, NVD (NIST), cvelistv5, CVE.org (MITRE)
Affected products
The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.
| Affected versions | Fixed in | ||
|---|---|---|---|
| Ubiquiti Inc | Cloud Gateways |
|
|
| Ubiquiti Inc | Cloud Keys |
|
|
| Ubiquiti Inc | Dream Machines |
|
|
| Ubiquiti Inc | Dream Routers |
|
|
| Ubiquiti Inc | Dream Wall |
|
|
| Ubiquiti Inc | Enterprise Firewall Core |
|
|
| Ubiquiti Inc | Enterprise Fortress Gateway |
|
|
| Ubiquiti Inc | Enterprise Video Recorders |
|
|
| Ubiquiti Inc | Express 7 |
|
|
| Ubiquiti Inc | Network Attached Storage |
|
|
| Ubiquiti Inc | Network Video Recorders |
|
|
| Ubiquiti Inc | UniFi OS Server |
|
|
| ui | unifi_os_server |
|
|
Vendors and products
- Ubiquiti Inc Cloud Gateways
- Ubiquiti Inc Cloud Keys
- Ubiquiti Inc Dream Machines
- Ubiquiti Inc Dream Routers
- Ubiquiti Inc Dream Wall
- Ubiquiti Inc Enterprise Firewall Core
- Ubiquiti Inc Enterprise Fortress Gateway
- Ubiquiti Inc Enterprise Video Recorders
- Ubiquiti Inc Express 7
- Ubiquiti Inc Network Attached Storage
- Ubiquiti Inc Network Video Recorders
- Ubiquiti Inc Unifi OS Server
Affected operating systems
| Other | ui | enterprise_firewall_core_firmware | — |
| Other | ui | enterprise_fortress_gateway_firmware | — |
| Other | ui | enterprise_network_video_recorder_core_firmware | — |
| Other | ui | enterprise_network_video_recorder_firmware | — |
| Other | ui | unas_2_firmware | — |
| Other | ui | unas_4_firmware | — |
| Other | ui | unas_pro_4_firmware | — |
| Other | ui | unas_pro_8_firmware | — |
| Other | ui | unas_pro_firmware | — |
| Other | ui | unifi_cloud_gateway_fiber_firmware | — |
| Other | ui | unifi_cloud_gateway_industrial_firmware | — |
| Other | ui | unifi_cloud_gateway_max_firmware | — |
| Other | ui | unifi_cloud_gateway_ultra_firmware | — |
| Other | ui | unifi_cloud_key_plus_firmware | — |
| Other | ui | unifi_cloudkey_enterprise_firmware | — |
| Other | ui | unifi_cloudkey_firmware | — |
| Other | ui | unifi_dream_machine_beast_firmware | — |
| Other | ui | unifi_dream_machine_firmware | — |
| Other | ui | unifi_dream_machine_pro_firmware | — |
| Other | ui | unifi_dream_machine_pro_max_firmware | — |
| Other | ui | unifi_dream_machine_special_edition_firmware | — |
| Other | ui | unifi_dream_router_5g_max_firmware | — |
| Other | ui | unifi_dream_router_7_firmware | — |
| Other | ui | unifi_dream_router_firmware | — |
Weakness classes (CWE)
CWE-918Server-Side Request Forgery (SSRF)
Base
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.
Entry at MITRE CWE-918
References & sources
- community.ui.comreleases/Security-Advisory-Bulletin-066-066/984eceb3-49c8-4227-…
Changes to this CVE
Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).
Record modifiedCISA ADP
CISA assessment (SSVC): exploitation: none known, automatable: no
Show the original change
Individual changes of this event as published by NVD Type Action Before After SSVC assessment added —{"id":"CVE-2026-54401","role":"CISA Coordinator","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"version":"2.0.3","timestamp":"2026-07-02T15:48:48.891370Z"}Source identifier: 134c704f-9b21-4f2e-91b3-4a467353bcc0
ReceivedHackerOne
CVSS V3.1: AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N
Weakness type: CWE-918
Description added or changed
Show 5 original changes
Individual changes of this event as published by NVD Type Action Before After Affected versions (publisher) added —UniFi OS Server, Dream Machines, Enterprise Fortress Gateway (+9)Description added —A malicious actor with access to the network and low privileges could exploit a Server-Side Request Forgery (SSRF) to escalate privileges within such UniFi OS devices or instances.CVSS added —AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:NWeakness type (CWE) added —CWE-918Reference added —https://community.ui.com/releases/Security-Advisory-Bulletin-066-066/984eceb3-49c8-4227-942d-671c289b3afcSource identifier: support@hackerone.com
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<a href="https://intel.neosec.eu/en/cve/CVE-2026-54401"><img src="https://intel.neosec.eu/badge/cve/CVE-2026-54401.svg?lang=en" alt="CVE-2026-54401 – NEOSEC Intel" height="20"></a>