diff --git a/lib/activitypub/federate.ts b/lib/activitypub/federate.ts
index de6f991..3746f4b 100644
--- a/lib/activitypub/federate.ts
+++ b/lib/activitypub/federate.ts
@@ -67,7 +67,9 @@ async function cacheActor(actorObject: ActorObject) {
 	actor.displayName = actorObject.name;
 	actor.inbox = actorObject.inbox;
 	actor.iconURL = iconURL;
-	actor.publicKeyPem = actorObject.publicKey.publicKeyPem;
+	if (actorObject.publicKey && actorObject.publicKey.publicKeyPem) {
+		actor.publicKeyPem = actorObject.publicKey.publicKeyPem;
+	}
 	actor.isFollower = false;
 	await getConnection().manager.save(actor);
 }
diff --git a/lib/activitypub/middleware/http-signature.ts b/lib/activitypub/middleware/http-signature.ts
index 4f583b8..f614ec4 100644
--- a/lib/activitypub/middleware/http-signature.ts
+++ b/lib/activitypub/middleware/http-signature.ts
@@ -25,7 +25,7 @@ export = async (req: Request, res: Response, next: NextFunction) => {
 				console.log(`Could not retrieve actor ${req.body.actor} to validate HTTP signature for`, req.body);
 				res.status(401).end("Could not retrieve actor to validate HTTP signature");
 			}
-		} else if (!validate(req, actor.publicKey.publicKeyPem)) {
+		} else if (!actor.publicKey || !actor.publicKey.publicKeyPem || !validate(req, actor.publicKey.publicKeyPem)) {
 			console.log(`Could not validate HTTP signature for ${req.body.actor}`);
 			res.status(401).end("Could not validate HTTP signature");
 		} else {