CVE-2026-34910

Ubiquiti UniFi OS command injection, confirmed exploited in the wild.

Ubiquiti UniFi OS contains an improper input validation vulnerability which could allow a malicious actor with access to the network to conduct command injection.

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90%chance of exploitation in the next 30 days (EPSS), 99th percentile

23 Junadded to CISA's Known Exploited Vulnerabilities list, 2026

26 Junfederal remediation deadline, already passed

Passedpast the deadline: patch now

CISA's name for it	Ubiquiti UniFi OS Improper Input Validation Vulnerability
Vendor and product	Ubiquiti · UniFi OS
Type	command injection · CWE-20
Exploited	Confirmed by CISA listed 23 June 2026
Likelihood	one of the most likely to be exploited of every vulnerability tracked
Deadline	26 June 2026 · already passed
Used in ransomware	Not reported
Advisories	community.ui.com ↗ · www.cisa.gov ↗ · www.cisa.gov ↗ · nvd.nist.gov ↗

What to do

Three steps, in this order

Step 1

Apply the vendor fix; command injection on an exposed device is used within days of disclosure.

Step 2

Restrict the management interface to a trusted network until the fix is in.

Step 3

Review the device's logs and configuration for changes you did not make.

CISA's required action	Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

CISA's required action

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

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Questions

CVE-2026-34910 in short

Is CVE-2026-34910 being exploited?

Yes. CISA added CVE-2026-34910 to its Known Exploited Vulnerabilities catalogue on 23 June 2026, which it does only on evidence of exploitation in the wild.

What is the CISA deadline for CVE-2026-34910?

US federal agencies must remediate it by 26 June 2026. Everyone else should treat that date as the latest safe point to patch an internet-facing system.

How likely is CVE-2026-34910 to be exploited in the next 30 days?

FIRST's Exploit Prediction Scoring System gives it 90%, the 99th percentile of every CVE it scores.

How do I fix CVE-2026-34910?

Apply the vendor fix; command injection on an exposed device is used within days of disclosure. Restrict the management interface to a trusted network until the fix is in. Review the device's logs and configuration for changes you did not make.

Same vendor

Other Ubiquiti vulnerabilities being exploited

CVE	Product	Type	Listed
CVE-2026-34909	UniFi OS	path traversal	23 June 2026
CVE-2026-34908	UniFi OS	exploited vulnerability	23 June 2026

Sources: CISA Known Exploited Vulnerabilities catalogue (released 10 November 2026) and FIRST EPSS. Page compiled automatically by SAK T.L.M, the threat-intelligence tool of SAK T.E.C, on 13 November 2026.