diff --git a/extensions/loom/sandbox/sandbox-config.ts b/extensions/loom/sandbox/sandbox-config.ts
index 8f303e8f..bface652 100644
--- a/extensions/loom/sandbox/sandbox-config.ts
+++ b/extensions/loom/sandbox/sandbox-config.ts
@@ -1,5 +1,6 @@
 import * as path from "path";
 import type { SandboxRuntimeConfig } from "@anthropic-ai/sandbox-runtime";
+import { normalizeGalaxyUrl } from "../profiles";
 
 /**
  * Inputs for deriving the OS-sandbox profile. Pure: no I/O, fully testable.
@@ -42,7 +43,14 @@ const DENY_WRITE = [".env", ".env.*", "*.pem", "*.key"];
 export function hostFromUrl(url?: string): string | undefined {
   if (!url) return undefined;
   try {
-    return new URL(url).hostname || undefined;
+    // Normalize via the same helper /connect and the profile system use, so a
+    // scheme-less GALAXY_URL ("usegalaxy.org") still resolves to a host.
+    const parsed = new URL(normalizeGalaxyUrl(url));
+    // Galaxy speaks http(s) only (validateGalaxyUrl enforces this on connect),
+    // so keep the host only for those schemes -- an ftp:// or file:// GALAXY_URL
+    // must not seed the bash network allowlist.
+    if (parsed.protocol !== "https:" && parsed.protocol !== "http:") return undefined;
+    return parsed.hostname || undefined;
   } catch {
     return undefined;
   }
diff --git a/tests/sandbox-config.test.ts b/tests/sandbox-config.test.ts
index bd74418e..cf79c313 100644
--- a/tests/sandbox-config.test.ts
+++ b/tests/sandbox-config.test.ts
@@ -8,6 +8,23 @@ describe("hostFromUrl", () => {
     expect(hostFromUrl("https://my.galaxy.example:8080/x")).toBe("my.galaxy.example");
     expect(hostFromUrl(undefined)).toBeUndefined();
     expect(hostFromUrl("not a url")).toBeUndefined();
+    expect(hostFromUrl("   ")).toBeUndefined();
+  });
+
+  it("extracts the host from a scheme-less URL (the form config/env often supply)", () => {
+    expect(hostFromUrl("usegalaxy.org")).toBe("usegalaxy.org");
+    expect(hostFromUrl("test.galaxyproject.org/")).toBe("test.galaxyproject.org");
+    expect(hostFromUrl("my.galaxy.example:8080/x")).toBe("my.galaxy.example");
+  });
+
+  it("keeps a loopback http host (the one non-https scheme Galaxy permits)", () => {
+    expect(hostFromUrl("http://127.0.0.1:8080")).toBe("127.0.0.1");
+  });
+
+  it("ignores non-http(s) schemes so they can't seed the network allowlist", () => {
+    // Galaxy speaks http(s); ftp:// / file:// (even with a host) must not allowlist one.
+    expect(hostFromUrl("ftp://x.org")).toBeUndefined();
+    expect(hostFromUrl("file://evil.example/etc/passwd")).toBeUndefined();
   });
 });
 
@@ -41,6 +58,11 @@ describe("buildSandboxConfig", () => {
     expect(c.network!.allowedDomains).toContain("usegalaxy.org");
   });
 
+  it("allowlists the Galaxy host even when the configured URL is scheme-less", () => {
+    const c = buildSandboxConfig({ ...base, galaxyUrl: "usegalaxy.org" });
+    expect(c.network!.allowedDomains).toContain("usegalaxy.org");
+  });
+
   it("includes extra write roots and extra allowed domains", () => {
     const c = buildSandboxConfig({
       ...base,