diff --git a/src/main/java/kjb/safedb/KjbNotRnnoJpaAttributeConverter.java b/src/main/java/kjb/safedb/KjbNotRnnoJpaAttributeConverter.java
index b5d84dc..4fcb331 100644
--- a/src/main/java/kjb/safedb/KjbNotRnnoJpaAttributeConverter.java
+++ b/src/main/java/kjb/safedb/KjbNotRnnoJpaAttributeConverter.java
@@ -1,19 +1,21 @@
 package kjb.safedb;
 
-import javax.persistence.AttributeConverter;
-import javax.persistence.Converter;
-
-import org.apache.commons.lang3.StringUtils;
-
 import com.eactive.ext.kjb.safedb.KjbSafedbWrapper;
 import com.eactive.ext.kjb.safedb.SafeDBColumns;
 import com.eactive.ext.kjb.safedb.Utils;
-
 import lombok.extern.slf4j.Slf4j;
+import org.apache.commons.lang3.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import javax.persistence.AttributeConverter;
+import javax.persistence.Converter;
 
 @Converter
 @Slf4j
 public class KjbNotRnnoJpaAttributeConverter implements AttributeConverter<String, String> {
+    private static final Logger needFixLogger = LoggerFactory.getLogger("eapim.portal.needfix");
+
     /**
      * 암호화
      * @param attribute  the entity attribute value to be converted
@@ -21,7 +23,7 @@ public class KjbNotRnnoJpaAttributeConverter implements AttributeConverter<Strin
      */
     @Override
     public String convertToDatabaseColumn(String attribute) {
-        log.debug("DB 암호화 #1 - {} / {}", attribute, SafeDBColumns.NOT_RNNO);
+//        log.debug("DB 암호화 #1 - {} / {}", attribute, SafeDBColumns.NOT_RNNO);
 
         String originalAttribute = attribute;
         if (StringUtils.isNotEmpty(attribute)) {
@@ -29,7 +31,7 @@ public class KjbNotRnnoJpaAttributeConverter implements AttributeConverter<Strin
             attribute = wrapper.encryptNotRnnoString(attribute);
         }
 
-        log.debug("DB 암호화 #2 : {} -> {}", originalAttribute, attribute);
+//        log.debug("DB 암호화 #2 : {} -> {}", originalAttribute, attribute);
 
         return attribute;
     }
@@ -42,19 +44,27 @@ public class KjbNotRnnoJpaAttributeConverter implements AttributeConverter<Strin
      */
     @Override
     public String convertToEntityAttribute(String dbData) {
-        log.debug("DB 복호화 #1 - {} / {}", dbData, SafeDBColumns.NOT_RNNO);
+//        log.debug("DB 복호화 #1 - {} / {}", dbData, SafeDBColumns.NOT_RNNO);
 
         String dbDataOriginal = dbData;
         if (StringUtils.isNotEmpty(dbData)) {
             if (this.isEncrypted(dbData)) {
                 KjbSafedbWrapper safeDBWrapper = KjbSafedbWrapper.getInstance();
-                dbData = safeDBWrapper.decryptNotRnno(dbData);
+                try {
+                    dbData = safeDBWrapper.decryptNotRnno(dbData);
+                } catch (Exception e) {
+                    // 복호화 실패시 원본 반환
+                    String logData = dbData.length() <= 3 ? dbData : dbData.substring(0, 3) + "...";
+                    log.warn("DB 복호화 실패: 복호화하지 않고 원본 반환. dbData={} (Length : {})",  logData, dbData.length());
+                    needFixLogger.warn("DB 복호화 실패: 복호화하지 않고 원본 반환. dbData={} (Length : {})",  logData, dbData.length(), e);
+                    return dbData;
+                }
             } else {
                 log.debug("DB 복호화 경고: Base64 형식이 아님. 복호화하지 않고 원본 반환. dbData={}", dbData);
             }
         }
 
-        log.debug("DB 복호화 #2 : {} -> {}", dbDataOriginal, dbData);
+//        log.debug("DB 복호화 #2 : {} -> {}", dbDataOriginal, dbData);
 
         return dbData;
     }
@@ -77,10 +87,16 @@ public class KjbNotRnnoJpaAttributeConverter implements AttributeConverter<Strin
         data = data.trim();
 
         // Base64 형식 체크
-        if (Utils.isBase64(data)) {
-            return true;
+        if (!Utils.isBase64(data)) {
+            return false;
         }
 
-        return false;
+        // Base64 길이 체크 (4의 배수)
+        if (data.length() % 4 != 0) {
+            return false;
+        }
+
+
+        return true;
     }
 }