diff --git a/core/src/main/java/org/keycloak/sdjwt/vp/SdJwtVP.java b/core/src/main/java/org/keycloak/sdjwt/vp/SdJwtVP.java
index 7c693a7f35..7b663ef02d 100644
--- a/core/src/main/java/org/keycloak/sdjwt/vp/SdJwtVP.java
+++ b/core/src/main/java/org/keycloak/sdjwt/vp/SdJwtVP.java
@@ -104,8 +104,16 @@ public class SdJwtVP {
         int disclosureStart = sdJwtString.indexOf(SdJwt.DELIMITER);
         int disclosureEnd = sdJwtString.lastIndexOf(SdJwt.DELIMITER);
 
+        if (disclosureStart == -1) {
+            throw new IllegalArgumentException("SD-JWT is malformed, expected to contain a '" + SdJwt.DELIMITER + "'");
+        }
+
         String issuerSignedJWTString = sdJwtString.substring(0, disclosureStart);
-        String disclosuresString = sdJwtString.substring(disclosureStart + 1, disclosureEnd);
+        String disclosuresString = "";
+
+        if (disclosureEnd > disclosureStart) {
+            disclosuresString = sdJwtString.substring(disclosureStart + 1, disclosureEnd);
+        }
 
         IssuerSignedJWT issuerSignedJWT = IssuerSignedJWT.fromJws(issuerSignedJWTString);
 
diff --git a/core/src/test/java/org/keycloak/sdjwt/sdjwtvp/SdJwtVPTest.java b/core/src/test/java/org/keycloak/sdjwt/sdjwtvp/SdJwtVPTest.java
index f787076b29..2ae3488431 100644
--- a/core/src/test/java/org/keycloak/sdjwt/sdjwtvp/SdJwtVPTest.java
+++ b/core/src/test/java/org/keycloak/sdjwt/sdjwtvp/SdJwtVPTest.java
@@ -32,6 +32,8 @@ import org.keycloak.sdjwt.vp.SdJwtVP;
 import java.util.Arrays;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.assertTrue;
 
 /**
@@ -196,4 +198,24 @@ public abstract class SdJwtVPTest {
                 .verifySignature(TestSettings.verifierContextFrom(presenteSdJwtVP.getCnfClaim(), "ES256"));
     }
 
+
+    @Test
+    public void testOf_validInput() {
+        String sdJwtString = TestUtils.readFileAsString(getClass(), "sdjwt/s6.2-presented-sdjwtvp.txt");
+        SdJwtVP sdJwtVP = SdJwtVP.of(sdJwtString);
+
+        assertNotNull(sdJwtVP);
+        assertEquals(4, sdJwtVP.getDisclosures().size());
+    }
+
+    @Test
+    public void testOf_MalformedSdJwt_ThrowsIllegalArgumentException() {
+        // Given
+        String malformedSdJwt = "issuer-signed-jwt";
+
+        // When & Then
+        IllegalArgumentException exception = assertThrows(IllegalArgumentException.class, () -> SdJwtVP.of(malformedSdJwt));
+        assertEquals("SD-JWT is malformed, expected to contain a '~'", exception.getMessage());
+    }
+
 }