diff --git a/tests/unit/security/certificate-fetcher-from-network.t.cpp b/tests/unit/security/certificate-fetcher-from-network.t.cpp
index 56677b7..8437c22 100644
--- a/tests/unit/security/certificate-fetcher-from-network.t.cpp
+++ b/tests/unit/security/certificate-fetcher-from-network.t.cpp
@@ -61,6 +61,7 @@
     cache.insert(subSubIdentity.getDefaultKey().getDefaultCertificate());
 
     m_keyChain.sign(data, signingByIdentity(subSubIdentity));
+    interest.setCanBePrefix(false);
     m_keyChain.sign(interest, signingByIdentity(subSubIdentity));
 
     processInterest = bind(&CertificateFetcherFromNetworkFixture<Response>::makeResponse, this, _1);