What it is
CVE-2026-34910 is an unauthenticated vulnerability affecting Ubiquiti UniFi OS Server and 30 other products. A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found...
Vulnerability report
UniFi OS Server Command Injection
Ubiquiti / UniFi OS Server · affected before 5.0.8
Decision summary
Direct answers before the deeper technical record.
What it is
CVE-2026-34910 is an unauthenticated vulnerability affecting Ubiquiti UniFi OS Server and 30 other products. A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found...
Is it exploited?
Yes. Previdian sensors observed exploitation attempts with confirmed confidence. Listed in CISA KEV. Also confirmed by third-party sources.
Who is affected?
Ubiquiti / UniFi OS Server affected before 5.0.8.
What should we do?
Patch immediately, validate internet-facing exposure, and monitor for matching requests.
Overview
A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found in UniFi OS devices to execute a Command Injection.
Exploitation evidence
Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.
Defused Cyber
A trusted third party reported exploitation.
Previdian sensor
Previdian first observed exploitation attempts targeting this vulnerability in our honeypot sensors.
Nuclei Templates
Public scanner or PoC coverage increases practical exploitability.
Per-source evidence links for KEV attestations are available through the Previdian Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| Defused Cyber First | 2026-06-09 08:18 UTC |
| Previdian Sensors | 2026-06-11 12:15 UTC |
| CISA | 2026-06-23 00:00 UTC |
| CVE | 2026-06-23 18:11 UTC |
| All CISA Advisories | 2026-06-23 18:20 UTC |
| The Shadowserver | 2026-07-08 00:00 UTC |
| The Hacker News | 2026-09-22 11:31 UTC |
Operational indicators for this CVE are listed under Detection.
Sensor telemetry
Previdian sensors recorded exploitation attempts targeting this vulnerability. The cards and chart show volume, unique attackers, and daily activity.
37
Attempts observed
17
Unique attacker IPs
9
Attacker countries
BG · CH · CN · FR · ID · JP · NL · SC · US
20
Sensors observed
CVE-2026-34910 exploitation attempts over the last 91 days
Daily events observed by Previdian sensors
Updated 22 Oct 2026
First observed 11 Jun 2026 · Last observed 22 Oct 2026
Pro adds sensor region and window summaries. Enterprise adds raw IPs, paths, User-Agents, and payloads.
Detection
Make the evidence actionable in scanner, SOC, and edge-control workflows.
Request targets and User-Agents available in Pro. Callback host details available in Enterprise.
Nuclei template detected 10 Jun 2026.
View Nuclei template (opens in new tab)Previdian virtual patch guidance is available for this CVE.
Attacker IP indicators observed · available in Pro and Enterprise.
Sensor-derived attacker IP indicators are available to Pro and Enterprise accounts under Detection and through the Pro API.
Learn about Pro API accessScanner and exploit-framework references linked to this CVE.
| Scanner | Reference | Detected |
|---|---|---|
| Nuclei | https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-34910.yaml | 10 Jun 2026 |
Compensating WAF rules for this CVE.
Enterprise feature. Virtual patch rule content and deployable vendor exports (ModSecurity, Cloudflare, AWS WAF) are available to Previdian Enterprise users.
Risk and context
CVSS v3.1
Potential damage if exploited. Separate from whether attackers are using it.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS
45.8%
Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.
Recent mention · The Hacker News
Ravie LakshmananSep 22, 2026Vulnerability / Endpoint Security The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Monday added a now-patched security flaw impacting Zyxel GS1900 series switches to its Known Exploited Vulnerabilities (KEV) catalog, citing...
Read full advisoryRecent mention · The Hacker News
Zyxel and Veeam Flaws Under Active Exploitation With Command and SYSTEM AccessThe Hacker News · 22 Sep 2026
Ravie LakshmananSep 22, 2026Vulnerability / Endpoint Security The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Monday added a now-patched security flaw impacting Zyxel GS1900 series switches to its Known Exploited Vulnerabilities (KEV) catalog, citing evidence of active exploitation. The vulnerability, tracked as CVE-2026-7273 (CVSS score: 8.8), is a stack-based buffer overflow vulnerability that could result in arbitrary operating system (OS) command execution. "A stack-based buffer overflow vulnerability in the CGI program of the Zyxel GS1900 series switch firmware...
Recent mention · GreyNoise
Open Season on Kapibala: Attacker Steals Over 18,000 Government Records Through WordPress ExploitationGreyNoise · 21 Sep 2026
GreyNoise has been tracking malicious use of an IP address since early June 2026 due to its frequent use in scans and attacks against a variety of technologies. We detail a few of the more notable intrusions we observed including the theft of more than 18,000 sensitive records from a western government.
Recent mention · All CISA Advisories
CISA Adds Four Known Exploited Vulnerabilities to CatalogAll CISA Advisories · 23 Jun 2026
CISA has added four new vulnerabilities to its Known Exploited Vulnerabilities (KEV) Catalog, based on evidence of active exploitation. CVE-2025-67038 Lantronix EDS5000 Code Injection Vulnerability CVE-2026-34908 Ubiquiti UniFi OS Improper Access Control Vulnerability CVE-2026-34909 Ubiquiti UniFi OS Path Traversal Vulnerability CVE-2026-34910 Ubiquiti UniFi OS Improper Input Validation Vulnerability These types of vulnerabilities are frequent attack vectors for malicious cyber actors and pose significant risks to the federal enterprise. Binding Operational Directive (BOD) 26-04:...
These PoCs are unverified and could contain malware. Use at your own risk.
github · Created 2026-08-22 11:22:33 UTC · 0 stars · AI assessment 90%
CVE-2026-34910 - CVE-2026-34909 Unifi OS
github · Created 2026-08-09 16:58:00 UTC · 2 stars · AI assessment 90%
CVE-2026-34910/34909 — UniFi OS unauth RCE + file read via ..%2f auth bypass (CVSS 10.0, KEV, Mirai ITW)
nuclei · Created Unknown
Timeline
11:31 UTC
Exploitation attested by an external source
00:00 UTC
Exploitation attested by an external source
18:20 UTC
Exploitation attested by an external source
18:11 UTC
Exploitation attested by an external source
00:00 UTC
Listed in the CISA Known Exploited Vulnerabilities catalog
14:21 UTC
Compensating WAF rule available to block exploitation
14:21 UTC
Public proof-of-concept code published
12:15 UTC
Indicators of compromise recorded
12:15 UTC
Evidence-backed exploitation signal
04:30 UTC
Scanner coverage available
08:18 UTC
High-confidence, third-party attested exploitation
00:43 UTC
Vulnerability disclosed publicly
15:00 UTC
Identifier reserved by the CNA
Pro API
Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
GET /api/v2/pro/kevs/CVE-2026-34910
Sample API response{
"cve_id": "CVE-2026-34910",
"confidence": "Confirmed",
"cvss_score": 10.0,
"cvss_estimated": false,
"epss_score": 0.45768,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": true
},
"sensor_telemetry": { "attempts": 37, "sensors": 20 }
}