diff --git a/tests/data_files/server10-badsign.crt b/tests/data_files/server10-badsign.crt
new file mode 100644
index 0000000..eca171f
--- /dev/null
+++ b/tests/data_files/server10-badsign.crt
@@ -0,0 +1,10 @@
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+-----END CERTIFICATE-----