CVE-2026-77539
CRITICALCVSS 9.1/10EPSS 0.81%
Last modified
CVE-2026-77539 is a critical-severity vulnerability rated 9.1/10 on the CVSS scale. A malicious actor with access to the network and high privileges could exploit an Improper Input Validation vulnerability found in UniFi OS Server to execute a Command Injection on the host device.. EPSS estimates a 0.81% chance of exploitation in the next 30 days.
Description
A malicious actor with access to the network and high privileges could exploit an Improper Input Validation vulnerability found in UniFi OS Server to execute a Command Injection on the host device.
Metrics
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Ubiquiti Inc | UniFi OS Server | < 5.1.37 |
References
Timeline
- Published
- Last Modified
- Status
- Deferred
Frequently Asked Questions
What is CVE-2026-77539?
A malicious actor with access to the network and high privileges could exploit an Improper Input Validation vulnerability found in UniFi OS Server to execute a Command Injection on the host device.
How severe is CVE-2026-77539?
CVE-2026-77539 has a CVSS score of 9.1/10 (CRITICAL severity). The EPSS model estimates a 0.81% probability of exploitation in the next 30 days.
How do I fix CVE-2026-77539?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
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Are you affected by CVE-2026-77539?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST