diff --git a/testdata/test_f4_sha256.x509.pem b/testdata/test_f4_sha256.x509.pem
new file mode 100644
index 0000000..9d5376b
--- /dev/null
+++ b/testdata/test_f4_sha256.x509.pem
@@ -0,0 +1,25 @@
+-----BEGIN CERTIFICATE-----
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+-----END CERTIFICATE-----