diff --git a/isoimagewriter/isoverifier.cpp b/isoimagewriter/isoverifier.cpp
--- a/isoimagewriter/isoverifier.cpp
+++ b/isoimagewriter/isoverifier.cpp
@@ -153,18 +153,34 @@
     GpgME::VerificationResult result = job->exec(signatureData, isoData.data());
     GpgME::Signature signature = result.signature(0);
 
-    if (signature.summary() == GpgME::Signature::None
-        && signature.fingerprint() == keyFingerprint) {
-        m_isIsoValid = true;
-    } else if (signature.summary() & GpgME::Signature::Valid) {
-        m_isIsoValid = true;
-    } else if (signature.summary() & GpgME::Signature::KeyRevoked) {
-        m_error = i18n("Key is revoked.");
-    } else {
-        m_error = i18n("Uses wrong signature.");
-    }
+    for (const auto &signature: result.signatures()) {
+        qDebug() << "signature summary" << signature.summary() << "status err code" << signature.status() << signature.status().asString()
+                             << "validity" << signature.validity() << "fingerprint" << signature.fingerprint();
 
-    emit finished(m_isIsoValid, m_error);
+        if (signature.summary() == GpgME::Signature::None && signature.summary() == GpgME::Signature::None) {
+            m_isIsoValid = true;
+        }
+        else if (signature.summary() & GpgME::Signature::Valid) {
+
+            m_isIsoValid = true;
+
+        } else if (signature.summary() & GpgME::Signature::KeyRevoked) {
+            m_error = i18n("Key is revoked.");
+        } else {
+            switch (signature.validity()) {
+                            case GpgME::Signature::Full:
+                            case GpgME::Signature::Ultimate:
+                            case GpgME::Signature::Never:
+                                m_error = i18n("Uses wrong signature.");
+                                break;
+                            case GpgME::Signature::Unknown:
+                            case GpgME::Signature::Undefined:
+
+                                m_isIsoValid = true;
+            }
+           }
+        }
+        emit finished(m_isIsoValid, m_error);
 }
 
 void IsoVerifier::verifyWithSha256SumsFile(const QString &keyFingerprint)