CVE-2026-77546Network attack vector

Authenticated command injection via improper input validation

Published Aug 26, 2026 · Updated Aug 26, 2026

Command injection in Ubiquiti UniFi Access Application 4.3.3 and earlier allows remote authenticated users to execute host commands. Ubiquiti attributes the flaw to improper input validation but has not disclosed the affected request, parameter, or code path. Low-privileged network access is required, and successful exploitation compromises confidentiality, integrity, and availability on the host device.

CVSS severity9.9
Critical
EPSS probability0.80%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Command injection in Ubiquiti UniFi Access Application 4.3.3 and earlier allows remote authenticated users to execute host commands. Ubiquiti attributes the flaw to improper input validation but has not disclosed the affected request, parameter, or code path. Low-privileged network access is required, and successful exploitation compromises confidentiality, integrity, and availability on the host device.

The record

CVE
CVE-2026-77546
Published
Aug 26, 2026
Updated
Aug 26, 2026
Vendor
Ubiquiti Inc.
Product
UniFi Access Application
Classifications
CWE-20, T1059
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 26, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 26, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <4.3.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Ubiquiti Inc. · UniFi Access Applicationversion=0 <4.3.5

Published CVSS scores

9.9UbiquitiCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1059Command and Scripting Interpreter

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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