Actively exploited
Listed in CISA’s Known Exploited Vulnerabilities catalog since June 23, 2026.
CVE-2026-34910
Ubiquiti UniFi OS Improper Input Validation Vulnerability
Ubiquiti · UniFi OS
Published July 21, 2026
What happened
Ubiquiti UniFi OS contains an improper input validation vulnerability which could allow a malicious actor with access to the network to conduct command injection.
What it means for your business
Ubiquiti UniFi OS is listed in CISA's Known Exploited Vulnerabilities catalog (CVE-2026-34910). Ubiquiti UniFi OS contains an improper input validation vulnerability which could allow a malicious actor with access to the network to conduct command injection. CISA remediation due date: 2026-06-26. PremierePC tracks KEV alerts for Upstate SC businesses — patch or open a ticket if you need help verifying exposure.
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 due date: June 26, 2026
Sources
Related briefs
CVE-2026-34908
Ubiquiti UniFi OS Improper Access Control Vulnerability
Ubiquiti UniFi OS is listed in CISA's Known Exploited Vulnerabilities catalog (CVE-2026-34908). Ubiquiti UniFi OS contains an improper access control vulnerability which could allow a malicious actor with access to the network to make unauthorized changes to the system. CISA remediation due date: 2026-06-26. PremierePC tracks KEV alerts for Upstate SC businesses — patch or open a ticket if you need help verifying exposure.
CVE-2026-34909
Ubiquiti UniFi OS Path Traversal Vulnerability
Ubiquiti UniFi OS is listed in CISA's Known Exploited Vulnerabilities catalog (CVE-2026-34909). Ubiquiti UniFi OS contains a path traversal vulnerability which could allow a malicious actor with access to the network to access files on the underlying system that could be manipulated to access an underlying account. CISA remediation due date: 2026-06-26. PremierePC tracks KEV alerts for Upstate SC businesses — patch or open a ticket if you need help verifying exposure.
CVE-2021-27137
DD-WRT Stack-Based Buffer Overflow Vulnerability
DD-WRT DD-WRT is listed in CISA's Known Exploited Vulnerabilities catalog (CVE-2021-27137). DD-WRT contains a stack-based buffer overflow vulnerability that could allow an unauthenticated attacker to overflow an internal buffer used by UPnP and trigger a code execution vulnerability. CISA remediation due date: 2026-07-24. PremierePC tracks KEV alerts for Upstate SC businesses — patch or open a ticket if you need help verifying exposure.
CVE-2023-4346
KNX Association KNX Protocol Connection Authorization Option 1 Overly Restrictive Account Lockout Mechanism Vulnerability
KNX Association KNX Protocol Connection Authorization Option 1 is listed in CISA's Known Exploited Vulnerabilities catalog (CVE-2023-4346). KNX Association KNX Protocol Connection Authorization Option 1 contains an overly restrictive account lockout mechanism vulnerability that could allow an attacker to purge all devices without additional security options enabled and set a BCU key to lock the device. CISA remediation due date: 2026-07-29. PremierePC tracks KEV alerts for Upstate SC businesses — patch or open a ticket if you need help verifying exposure.
Need help patching?
PremierePC monitors KEV alerts for managed clients and helps teams prioritize remediation before attackers do.