diff --git a/packages/snaps-controllers/src/services/iframe/IframeExecutionService.ts b/packages/snaps-controllers/src/services/iframe/IframeExecutionService.ts
index 71812eb559..1986de58d2 100644
--- a/packages/snaps-controllers/src/services/iframe/IframeExecutionService.ts
+++ b/packages/snaps-controllers/src/services/iframe/IframeExecutionService.ts
@@ -30,7 +30,17 @@ export class IframeExecutionService extends AbstractExecutionService<Window> {
   }
 
   protected terminateJob(jobWrapper: TerminateJobArgs<Window>): void {
-    document.getElementById(jobWrapper.id)?.remove();
+    const iframe = document.getElementById(
+      jobWrapper.id,
+    ) as HTMLIFrameElement | null;
+    if (iframe) {
+      // Navigate to about:blank before removing to ensure the browser
+      // unloads the previous document and cleans up its event listeners.
+      // Without this, Firefox may keep the detached iframe's document alive
+      // with all its event listeners, causing a memory leak.
+      iframe.src = 'about:blank';
+      iframe.remove();
+    }
   }
 
   protected async initEnvStream(snapId: string): Promise<{
diff --git a/packages/snaps-execution-environments/src/common/BaseSnapExecutor.ts b/packages/snaps-execution-environments/src/common/BaseSnapExecutor.ts
index 3818439f46..3feb6edac2 100644
--- a/packages/snaps-execution-environments/src/common/BaseSnapExecutor.ts
+++ b/packages/snaps-execution-environments/src/common/BaseSnapExecutor.ts
@@ -486,6 +486,19 @@ export class BaseSnapExecutor {
       data.runningEvaluations.forEach((evaluation) => evaluation.stop()),
     );
     this.snapData.clear();
+
+    // Clean up global error handlers to prevent memory leaks.
+    // Without this, the event listeners keep references to the executor
+    // and prevent the iframe from being garbage collected.
+    if (this.snapPromiseErrorHandler) {
+      removeEventListener('unhandledrejection', this.snapPromiseErrorHandler);
+      this.snapPromiseErrorHandler = undefined;
+    }
+
+    if (this.snapErrorHandler) {
+      removeEventListener('error', this.snapErrorHandler);
+      this.snapErrorHandler = undefined;
+    }
   }
 
   // TODO: Either fix this lint violation or explain why it's necessary to