diff --git a/src/journal/fuzz-journald-kmsg.c b/src/journal/fuzz-journald-kmsg.c
index 1b423d5cba..ec22f14ccb 100644
--- a/src/journal/fuzz-journald-kmsg.c
+++ b/src/journal/fuzz-journald-kmsg.c
@@ -10,6 +10,11 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size) {
         if (size == 0)
                 return 0;
 
+        /* We don't want to fill the logs with assert warnings.
+         * Disable most logging if not running standalone */
+        if (!getenv("SYSTEMD_LOG_LEVEL"))
+                log_set_max_level(LOG_CRIT);
+
         dummy_server_init(&s, data, size);
         dev_kmsg_record(&s, s.buffer, size);
         server_done(&s);