Executive Summary
Bifrost, an open-source AI gateway for 20+ LLM providers, has critical CVE-2026-90898 (CVSS 9.8) allowing unauthenticated command execution before 2.1.0 when management auth is off.
What Happened
A critical vulnerability in Bifrost, an open-source AI gateway that routes requests to more than 20 LLM providers, allows an unauthenticated attacker to run arbitrary commands on the gateway server with a single HTTP request. The flaw, tracked as CVE-2026-90898 (CVSS score: 9.8), affects all versions of the Bifrost HTTP transport before 2.1.0 when management authentication is
Affected Products
- Bifrost AI gateway
Vulnerability / Attack Technique
Unauthenticated RCE in an AI gateway
Technical Mechanism
A single request can run commands when management authentication is disabled.
AI Security Category
LLM03:2025 Supply Chain
Part of the AI Supply Chain and AI SBOM topic.
Relevant Frameworks
RealGround Analysis
AI gateways hold every provider key. RealGround analysis: enable management auth and upgrade.
Recommended Controls
- Upgrade Bifrost to 2.1.0
- Enable management authentication
- Rotate provider keys if exposed
Related RealGround Service
AI Agent SBOM and LLM Mapping · or start with the free AI Agent Security Scanner.
Sources
thehackernews.com: https://thehackernews.com/2026/09/critical-bifrost-ai-gateway-flaw-lets.html
Summary and analysis written by RealGround from the source above; last updated 2026-10-18.