diff --git a/backend/src/services/app-connection/hc-vault/hc-vault-connection-fns.ts b/backend/src/services/app-connection/hc-vault/hc-vault-connection-fns.ts
index 38f97700c..425c9c4d2 100644
--- a/backend/src/services/app-connection/hc-vault/hc-vault-connection-fns.ts
+++ b/backend/src/services/app-connection/hc-vault/hc-vault-connection-fns.ts
@@ -25,6 +25,23 @@ import {
   THCVaultMountResponse
 } from "./hc-vault-connection-types";
 
+// HashiCorp Vault stores JSON data, so values can be any valid JSON type
+type JsonValue = string | number | boolean | null | JsonValue[] | { [key: string]: JsonValue };
+
+export const convertVaultValueToString = (value: JsonValue): string => {
+  if (value === null) {
+    return "";
+  }
+  if (typeof value === "string") {
+    return value;
+  }
+  if (typeof value === "number" || typeof value === "boolean") {
+    return String(value);
+  }
+  // For objects and arrays, serialize as JSON
+  return JSON.stringify(value);
+};
+
 // Concurrency limit for HC Vault API requests to avoid rate limiting
 const HC_VAULT_CONCURRENCY_LIMIT = 20;
 
@@ -598,7 +615,7 @@ export const getHCVaultSecretsForPath = async (
       // For KV v2: /v1/{mount}/data/{path}
       const { data } = await requestWithHCVaultGateway<{
         data: {
-          data: Record<string, string>; // KV v2 has nested data structure
+          data: Record<string, JsonValue>; // KV v2 has nested data structure, supports all JSON types
           metadata: {
             created_time: string;
             deletion_time: string;
@@ -620,7 +637,7 @@ export const getHCVaultSecretsForPath = async (
 
     // For KV v1: /v1/{mount}/{path}
     const { data } = await requestWithHCVaultGateway<{
-      data: Record<string, string>; // KV v1 has flat data structure
+      data: Record<string, JsonValue>; // KV v1 has flat data structure, supports all JSON types
       lease_duration: number;
       lease_id: string;
       renewable: boolean;
diff --git a/backend/src/services/external-migration/external-migration-service.ts b/backend/src/services/external-migration/external-migration-service.ts
index 3cc128768..bc2a24c07 100644
--- a/backend/src/services/external-migration/external-migration-service.ts
+++ b/backend/src/services/external-migration/external-migration-service.ts
@@ -16,6 +16,7 @@ import { AppConnection } from "../app-connection/app-connection-enums";
 import { decryptAppConnectionCredentials } from "../app-connection/app-connection-fns";
 import { TAppConnectionServiceFactory } from "../app-connection/app-connection-service";
 import {
+  convertVaultValueToString,
   getHCVaultAuthMounts,
   getHCVaultKubernetesAuthRoles,
   getHCVaultSecretsForPath,
@@ -592,7 +593,7 @@ export const externalMigrationServiceFactory = ({
         projectId,
         secrets: Object.entries(vaultSecrets).map(([secretKey, secretValue]) => ({
           secretKey,
-          secretValue
+          secretValue: convertVaultValueToString(secretValue)
         }))
       });