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VULNERABILITY BRIEF 🟡 Medium Vulnerability

Ubiquiti AI Pro Discovery Protocol Downgrade Vulnerability (CVE‑2026‑21633)

This vulnerability allows network-adjacent attackers to downgrade the communication protocol on affected installations of Ubiquiti Networks AI Pro. Authentication is not required to exploit this vulnerability. The ZDI has assigned a CVSS rating of 5.4. The following CVEs are assigned: CVE-2026-21633.

Verisq™ Intelligence · 📅 March 05, 2026 · 📰 zerodayinitiative.com
🟡
Severity
Medium
VU
Type
Vulnerability
🎯
Confidence
High
🏢
Affected
2 sector(s)
✅
Actions
5 recommended
📰
Source
zerodayinitiative.com

LiveThreat Vulnerability Brief — CVE-2026-21633

What It Is — A missing‑encryption flaw in the Ubiquiti AI Pro discovery protocol permits unauthenticated, network‑adjacent attackers to downgrade the communication protocol to an unencrypted mode. Exploitability — Proof‑of‑concept code is publicly available; no known active ransomware‑style exploit, CVSS 5.4 (Moderate).

Affected Products — Ubiquiti Networks AI Pro devices.

TPRM Impact — Organizations that embed AI Pro in their infrastructure face potential data exposure and downstream service manipulation, creating a supply‑chain risk for third‑party customers.

Recommended Actions — Deploy Ubiquiti’s security patch immediately; if patching is delayed, disable the discovery protocol, segment AI Pro devices onto isolated VLANs, monitor for protocol‑downgrade traffic, and update asset inventories. Source: Zero Day Initiative advisory

📰 Original Source
http://www.zerodayinitiative.com/advisories/ZDI-26-126/ ↗

This Verisq Intelligence Brief is an independent analysis. Read the original reporting at the link above.

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