diff --git a/files/routes/admin.py b/files/routes/admin.py
index 75386b72d0..66bbedacaa 100644
--- a/files/routes/admin.py
+++ b/files/routes/admin.py
@@ -1515,9 +1515,12 @@ def ban_domain(v):
 	domain=request.values.get("domain", "").strip().lower()
 	if not domain: abort(400)
 
-	reason=request.values.get("reason").strip()
+	reason=request.values.get("reason", "").strip()
 	if not reason: abort(400, 'Reason is required!')
 
+	if len(reason) > 100:
+		abort(400, 'Reason is too long (max 100 characters)!')
+
 	existing = g.db.get(BannedDomain, domain)
 	if not existing:
 		d = BannedDomain(domain=domain, reason=reason)