CVE-2026-55641: high-severity vulnerability in decolua 9router
9router: Unauthenticated `/v1` proxy access via `Host`-header spoofing → open AI relay + SSRF
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 8.2epss 0.3%
9Router is an AI router & token saver. Prior to 0.5.2, 9router determines whether a /v1 LLM proxy request is local by reading the client-controlled Host header, allowing a remote unauthenticated attacker to send Host: localhost and bypass API-key authentication. In the default configuration, this exposes the /v1 proxy to upstream provider calls using stored provider credentials and allows /v1/search with the searxng provider_options.baseUrl parameter to drive server-side requests to internal or cloud-metadata hosts. This issue is fixed in version 0.5.2.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
Affected products
decolua · 9routerRelated CVEs — decolua 9router
In the same product, most dangerous first.
CVE-2026-55638HIGH9router: Unauthenticated LLM proxy access via /codex rewrite authorization bypassEPSS 6.6%CVE-2026-46339CRITICAL9Router: Unauthenticated Remote Code Execution via unprotected MCP custom plugin routesEPSS 2.8%CVE-2026-59800CRITICAL9Router < 0.4.44 - OS Command Injection via sudoPassword Parameter in Tailscale Install EndpointEPSS 2.1%CVE-2026-56681HIGH9Router: Authentication Bypass in Public LLM API via Spoofable X-9r-Real-Ip HeaderEPSS 1.1%CVE-2026-63732CRITICAL9router before 0.4.60 Remote Code Execution via default passwordEPSS 1.0%CVE-2026-62312HIGH9Router: Authenticated RCE via Unvalidated MCP Plugin ArgumentsEPSS 0.9%