diff --git a/tests/unit/security/certificate-fetcher-direct-fetch.t.cpp b/tests/unit/security/certificate-fetcher-direct-fetch.t.cpp
index 9f8c24f..25e0be5 100644
--- a/tests/unit/security/certificate-fetcher-direct-fetch.t.cpp
+++ b/tests/unit/security/certificate-fetcher-direct-fetch.t.cpp
@@ -73,7 +73,9 @@
     cache.insert(subSubIdentity.getDefaultKey().getDefaultCertificate());
 
     m_keyChain.sign(data, signingByIdentity(subSubIdentity));
+    interest.setCanBePrefix(false);
     m_keyChain.sign(interest, signingByIdentity(subSubIdentity));
+    interestNoTag.setCanBePrefix(false);
     m_keyChain.sign(interestNoTag, signingByIdentity(subSubIdentity));
 
     data.setTag(make_shared<lp::IncomingFaceIdTag>(123));