diff --git a/files/routes/admin.py b/files/routes/admin.py
index 4bbf67634..e8cd15440 100644
--- a/files/routes/admin.py
+++ b/files/routes/admin.py
@@ -1018,6 +1018,9 @@ def ban_user(id, v):
 	except:
 		pass
 
+	if days < 0:
+		abort(400, "You can't bans people for negative days!")
+
 	reason = request.values.get("reason", "").strip()[:256]
 
 	if not reason:
@@ -1099,6 +1102,9 @@ def agendaposter(id, v):
 	except:
 		pass
 
+	if days < 0:
+		abort(400, "You can't chud people for negative days!")
+
 	reason = request.values.get("reason", "").strip()
 
 	reason = filter_emojis_only(reason)