diff --git a/packages/control-plane/src/sandbox/lifecycle/manager.test.ts b/packages/control-plane/src/sandbox/lifecycle/manager.test.ts
index 960241cf5..460b0c5aa 100644
--- a/packages/control-plane/src/sandbox/lifecycle/manager.test.ts
+++ b/packages/control-plane/src/sandbox/lifecycle/manager.test.ts
@@ -679,6 +679,33 @@ describe("SandboxLifecycleManager", () => {
       expect(storage.calls).toContain("updateSandboxStatus:failed");
     });
 
+    it("fails spawn when getUserEnvVars rejects", async () => {
+      const sandbox = createMockSandbox({ status: "pending", created_at: Date.now() - 60000 });
+      const storage = createMockStorage(createMockSession(), sandbox);
+      storage.getUserEnvVars = vi.fn(async () => {
+        throw new Error("D1 decryption failure");
+      });
+      const broadcaster = createMockBroadcaster();
+      const wsManager = createMockWebSocketManager(false);
+      const provider = createMockProvider();
+
+      const manager = new SandboxLifecycleManager(
+        provider,
+        storage,
+        broadcaster,
+        wsManager,
+        createMockAlarmScheduler(),
+        createMockIdGenerator(),
+        createTestConfig()
+      );
+
+      await manager.spawnSandbox();
+
+      expect(provider.createSandbox).not.toHaveBeenCalled();
+      expect(storage.calls).toContain("updateSandboxStatus:failed");
+      expect(manager.isSpawning()).toBe(false);
+    });
+
     it("skips spawn when already spawning", async () => {
       const sandbox = createMockSandbox({ status: "spawning" });
       const storage = createMockStorage(createMockSession(), sandbox);
diff --git a/packages/control-plane/src/session/durable-object.ts b/packages/control-plane/src/session/durable-object.ts
index d535f215a..eaae33cf5 100644
--- a/packages/control-plane/src/session/durable-object.ts
+++ b/packages/control-plane/src/session/durable-object.ts
@@ -1686,30 +1686,13 @@ export class SessionDO extends DurableObject<Env> {
       return undefined;
     }
 
-    // Fetch global secrets
-    let globalSecrets: Record<string, string> = {};
-    try {
-      const globalStore = new GlobalSecretsStore(this.env.DB, this.env.REPO_SECRETS_ENCRYPTION_KEY);
-      globalSecrets = await globalStore.getDecryptedSecrets();
-    } catch (e) {
-      this.log.error("Failed to load global secrets, proceeding without", {
-        error: e instanceof Error ? e.message : String(e),
-      });
-    }
+    // Fail hard on secret loading — sandboxes must not silently lose secrets
+    const globalStore = new GlobalSecretsStore(this.env.DB, this.env.REPO_SECRETS_ENCRYPTION_KEY);
+    const globalSecrets = await globalStore.getDecryptedSecrets();
 
-    // Fetch repo secrets
-    let repoSecrets: Record<string, string> = {};
-    try {
-      const repoId = await this.ensureRepoId(session);
-      const repoStore = new RepoSecretsStore(this.env.DB, this.env.REPO_SECRETS_ENCRYPTION_KEY);
-      repoSecrets = await repoStore.getDecryptedSecrets(repoId);
-    } catch (e) {
-      this.log.warn("Failed to load repo secrets, proceeding without", {
-        repo_owner: session.repo_owner,
-        repo_name: session.repo_name,
-        error: e instanceof Error ? e.message : String(e),
-      });
-    }
+    const repoId = await this.ensureRepoId(session);
+    const repoStore = new RepoSecretsStore(this.env.DB, this.env.REPO_SECRETS_ENCRYPTION_KEY);
+    const repoSecrets = await repoStore.getDecryptedSecrets(repoId);
 
     // Merge: repo overrides global
     const { merged, totalBytes, exceedsLimit } = mergeSecrets(globalSecrets, repoSecrets);