diff --git a/packages/aws-cdk/lib/cli/cdk-toolkit.ts b/packages/aws-cdk/lib/cli/cdk-toolkit.ts
index 400a77987..eb3b0294e 100644
--- a/packages/aws-cdk/lib/cli/cdk-toolkit.ts
+++ b/packages/aws-cdk/lib/cli/cdk-toolkit.ts
@@ -256,8 +256,18 @@ export class CdkToolkit {
   }
 
   public async acknowledge(noticeId: string) {
+    const issueNumber = Number(noticeId);
+    if (!Number.isInteger(issueNumber)) {
+      throw new ToolkitError(
+        'InvalidAcknowledgementId',
+        `Invalid notice ID '${noticeId}': 'cdk acknowledge' only accepts numeric notice IDs (e.g. 'cdk acknowledge 12345'). ` +
+        'Scoped construct warnings such as \'@aws-cdk/aws-ecs:minHealthyPercent\' are acknowledged in code with ' +
+        'Annotations.of(scope).acknowledgeWarning(\'<id>\').',
+      );
+    }
+
     const acks = new Set(this.props.configuration.context.get('acknowledged-issue-numbers') ?? []);
-    acks.add(Number(noticeId));
+    acks.add(issueNumber);
     this.props.configuration.context.set('acknowledged-issue-numbers', Array.from(acks));
     await this.props.configuration.saveContext();
   }
diff --git a/packages/aws-cdk/test/commands/acknowledge.test.ts b/packages/aws-cdk/test/commands/acknowledge.test.ts
index 300a749b9..a58ad375d 100644
--- a/packages/aws-cdk/test/commands/acknowledge.test.ts
+++ b/packages/aws-cdk/test/commands/acknowledge.test.ts
@@ -29,4 +29,16 @@ describe('acknowledge command', () => {
     // THEN
     expect(configuration.context.get('acknowledged-issue-numbers')).toEqual([12345]);
   });
+
+  test('acknowledging a scoped construct warning id throws and does not corrupt the context', async () => {
+    // WHEN / THEN
+    await expect(toolkit.acknowledge('@aws-cdk/aws-ecs:minHealthyPercent')).rejects.toThrow(/numeric notice IDs/i);
+
+    // AND the context is not corrupted with a `null` entry
+    expect(configuration.context.get('acknowledged-issue-numbers')).toBeUndefined();
+  });
+
+  test('acknowledging a non-numeric id throws', async () => {
+    await expect(toolkit.acknowledge('not-a-number')).rejects.toThrow(/Invalid notice ID/i);
+  });
 });