What’s Vulnerable › Vulnerabilities
CVE-2026-77555
- Severity: high (CVSS 7.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.5% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-09-22 · updated 2026-09-22
- Weakness: CWE-787
Description
A malicious actor with access to the network could exploit an Out-of-bounds Write vulnerability found in certain UniFi gateway devices to execute a Denial of Service (DoS) attack on the device.
Affected products
- Ubiquiti Inc Cloud Gateways: before 5.1.31 — fixed in 5.1.31
- Ubiquiti Inc Dream Machines: before 5.1.31 — fixed in 5.1.31
- Ubiquiti Inc Dream Routers: before 5.1.31 — fixed in 5.1.31
- Ubiquiti Inc Dream Wall: before 5.1.31 — fixed in 5.1.31
- Ubiquiti Inc Enterprise Firewalls: before 5.1.31 — fixed in 5.1.31
- Ubiquiti Inc Express: before 4.0.21 — fixed in 4.0.21
- Ubiquiti Inc Express 7: before 5.1.31 — fixed in 5.1.31
- Ubiquiti Inc UniFi Gateways: before 5.1.26 — fixed in 5.1.26
How to fix
Upgrade to a fixed version: Ubiquiti Inc Cloud Gateways 5.1.31; Ubiquiti Inc Dream Machines 5.1.31; Ubiquiti Inc Dream Routers 5.1.31; Ubiquiti Inc Dream Wall 5.1.31; Ubiquiti Inc Enterprise Firewalls 5.1.31; Ubiquiti Inc Express 4.0.21; Ubiquiti Inc Express 7 5.1.31; Ubiquiti Inc UniFi Gateways 5.1.26. Check the vendor advisory for mitigations.
References
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