diff --git a/src/main/java/org/ohdsi/webapi/DataAccessConfig.java b/src/main/java/org/ohdsi/webapi/DataAccessConfig.java
index 601399621..9d638131b 100644
--- a/src/main/java/org/ohdsi/webapi/DataAccessConfig.java
+++ b/src/main/java/org/ohdsi/webapi/DataAccessConfig.java
@@ -3,6 +3,7 @@
 import com.cosium.spring.data.jpa.entity.graph.repository.support.EntityGraphJpaRepositoryFactoryBean;
 import org.ohdsi.webapi.arachne.encryption.EncryptorUtils;
 import org.ohdsi.webapi.arachne.encryption.NotEncrypted;
+import org.ohdsi.webapi.source.EncryptedStringConverter;
 import org.jasypt.encryption.pbe.PBEStringEncryptor;
 import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
 import org.springframework.orm.hibernate5.SpringBeanContainer;
@@ -134,6 +135,7 @@ public PBEStringEncryptor defaultStringEncryptor(){
         PBEStringEncryptor stringEncryptor = encryptorEnabled ?
                 EncryptorUtils.buildStringEncryptor(env) :
                 new NotEncrypted();
+        EncryptedStringConverter.setDefaultEncryptor(stringEncryptor);
 
         return stringEncryptor;
     }
diff --git a/src/main/java/org/ohdsi/webapi/source/EncryptedStringConverter.java b/src/main/java/org/ohdsi/webapi/source/EncryptedStringConverter.java
index 2b364867e..2166ef5b2 100644
--- a/src/main/java/org/ohdsi/webapi/source/EncryptedStringConverter.java
+++ b/src/main/java/org/ohdsi/webapi/source/EncryptedStringConverter.java
@@ -15,20 +15,27 @@
  *
  * Spring/Hibernate integration note:
  * By default, Hibernate instantiates @Converter classes via reflection (newInstance()),
- * bypassing Spring dependency injection entirely. To solve this, DataAccessConfig registers
- * a SpringBeanContainer via the "hibernate.resource.beans.container" property on the
- * EntityManagerFactory. This tells Hibernate to resolve managed beans (including this
- * converter) from the Spring ApplicationContext, so @Autowired injection works naturally.
+ * bypassing Spring dependency injection entirely. DataAccessConfig registers a
+ * SpringBeanContainer so Hibernate resolves the converter from the ApplicationContext, but
+ * that is not guaranteed to run @Autowired either: in the GraalVM native image the setter
+ * is never invoked and the encryptor stayed null, so encrypted ENC(...) credentials were
+ * handed to the JDBC driver as-is. The encryptor is therefore held statically and set
+ * directly by the defaultStringEncryptor bean, so every instance sees it however it was
+ * created. A missing encryptor fails loudly instead of silently skipping encryption.
  */
 @Component
 @Converter
 public class EncryptedStringConverter implements AttributeConverter<String, String> {
 
-    private PBEStringEncryptor encryptor;
+    private static volatile PBEStringEncryptor encryptor;
+
+    public static void setDefaultEncryptor(PBEStringEncryptor defaultStringEncryptor) {
+        encryptor = defaultStringEncryptor;
+    }
 
     @Autowired
     public void setEncryptor(PBEStringEncryptor defaultStringEncryptor) {
-        this.encryptor = defaultStringEncryptor;
+        setDefaultEncryptor(defaultStringEncryptor);
     }
 
     @Override
@@ -36,7 +43,7 @@ public String convertToDatabaseColumn(String attribute) {
         if (attribute == null) {
             return null;
         }
-        return EncryptorUtils.encrypt(encryptor, attribute);
+        return EncryptorUtils.encrypt(requireEncryptor(), attribute);
     }
 
     @Override
@@ -44,6 +51,14 @@ public String convertToEntityAttribute(String dbData) {
         if (dbData == null) {
             return null;
         }
-        return EncryptorUtils.decrypt(encryptor, dbData);
+        return EncryptorUtils.decrypt(requireEncryptor(), dbData);
+    }
+
+    private static PBEStringEncryptor requireEncryptor() {
+        PBEStringEncryptor current = encryptor;
+        if (current == null) {
+            throw new IllegalStateException("EncryptedStringConverter has no encryptor: the defaultStringEncryptor bean has not been created");
+        }
+        return current;
     }
 }
diff --git a/src/test/java/org/ohdsi/webapi/source/EncryptedStringConverterTest.java b/src/test/java/org/ohdsi/webapi/source/EncryptedStringConverterTest.java
new file mode 100644
index 000000000..38f9b5b92
--- /dev/null
+++ b/src/test/java/org/ohdsi/webapi/source/EncryptedStringConverterTest.java
@@ -0,0 +1,61 @@
+package org.ohdsi.webapi.source;
+
+import org.jasypt.encryption.pbe.StandardPBEStringEncryptor;
+import org.junit.After;
+import org.junit.Test;
+
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.not;
+import static org.hamcrest.Matchers.startsWith;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertThrows;
+
+public class EncryptedStringConverterTest {
+
+    @After
+    public void resetEncryptor() {
+        EncryptedStringConverter.setDefaultEncryptor(null);
+    }
+
+    private static StandardPBEStringEncryptor encryptor() {
+        StandardPBEStringEncryptor encryptor = new StandardPBEStringEncryptor();
+        encryptor.setPassword("test-password");
+        return encryptor;
+    }
+
+    @Test
+    public void converterCreatedWithoutInjectionDecrypts() {
+        EncryptedStringConverter.setDefaultEncryptor(encryptor());
+
+        // Hibernate may instantiate the converter itself, so @Autowired never runs on it.
+        EncryptedStringConverter converter = new EncryptedStringConverter();
+        String stored = converter.convertToDatabaseColumn("secret");
+
+        assertThat(stored, startsWith("ENC("));
+        assertThat(new EncryptedStringConverter().convertToEntityAttribute(stored), is("secret"));
+    }
+
+    @Test
+    public void encryptedValueIsNotPassedThroughWithoutEncryptor() {
+        String stored = "ENC(" + encryptor().encrypt("secret") + ")";
+
+        assertThrows(IllegalStateException.class,
+                () -> new EncryptedStringConverter().convertToEntityAttribute(stored));
+    }
+
+    @Test
+    public void plaintextIsNotStoredWithoutEncryptor() {
+        assertThrows(IllegalStateException.class,
+                () -> new EncryptedStringConverter().convertToDatabaseColumn("secret"));
+    }
+
+    @Test
+    public void autowiredSetterSharesEncryptorWithOtherInstances() {
+        new EncryptedStringConverter().setEncryptor(encryptor());
+
+        String stored = new EncryptedStringConverter().convertToDatabaseColumn("secret");
+
+        assertThat(stored, not(is("secret")));
+        assertThat(new EncryptedStringConverter().convertToEntityAttribute(stored), is("secret"));
+    }
+}