diff --git a/app/components/storage/SiteSyncCard.vue b/app/components/storage/SiteSyncCard.vue
index 08dd711..99889d5 100644
--- a/app/components/storage/SiteSyncCard.vue
+++ b/app/components/storage/SiteSyncCard.vue
@@ -60,8 +60,12 @@ const isPull = computed(() => direction.value === 'pull')
 const canAbandon = computed(() =>
   !props.busy
   && Boolean(props.resumableJob)
-  && (isPull.value || Boolean(token.value.trim()))
 )
+const abandonConfirm = computed(() => (
+  isPull.value || token.value.trim()
+    ? t('storage.backup.siteSyncAbandonConfirm')
+    : t('storage.backup.siteSyncAbandonWithoutTokenConfirm')
+))
 const directionSubtitle = computed(() => (
   isPull.value
     ? t('storage.backup.siteSyncPullSubtitle')
@@ -110,7 +114,7 @@ function resumeSync() {
 
 function abandonSync() {
   if (!canAbandon.value || !props.resumableJob) return
-  if (!window.confirm(t('storage.backup.siteSyncAbandonConfirm'))) return
+  if (!window.confirm(abandonConfirm.value)) return
   emit('sync', {
     targetBaseUrl: targetBaseUrl.value.trim(),
     token: token.value.trim(),
diff --git a/app/composables/useBackup.ts b/app/composables/useBackup.ts
index 6a286a5..8a271a7 100644
--- a/app/composables/useBackup.ts
+++ b/app/composables/useBackup.ts
@@ -268,11 +268,17 @@ export function useBackup() {
       )
       await refreshJobsFirstPage()
       startPolling()
+      const cleanupPending = Boolean(
+        body.abandonJobId
+        && data.job.payload.cleanupPending === true
+      )
       toast.add({
-        title: body.abandonJobId
-          ? t('storage.backup.siteSyncAbandoned')
-          : t('storage.backup.siteSyncStarted'),
-        color: 'success'
+        title: cleanupPending
+          ? t('storage.backup.siteSyncAbandonedPendingCleanup')
+          : body.abandonJobId
+            ? t('storage.backup.siteSyncAbandoned')
+            : t('storage.backup.siteSyncStarted'),
+        color: cleanupPending ? 'warning' : 'success'
       })
       return data.job
     } catch (error: unknown) {
diff --git a/i18n/locales/en.json b/i18n/locales/en.json
index 5e12c42..65d5e4d 100644
--- a/i18n/locales/en.json
+++ b/i18n/locales/en.json
@@ -695,7 +695,9 @@
       "siteSyncResume": "Resume last sync",
       "siteSyncAbandon": "Abandon and clean up",
       "siteSyncAbandonConfirm": "Abandon this sync and delete partial objects created by it that are not yet referenced by a media record?",
+      "siteSyncAbandonWithoutTokenConfirm": "No target token is provided. Abandon the task now? Partial objects will be marked for later automatic cleanup on the target.",
       "siteSyncAbandoned": "Sync abandoned and partial objects cleaned up",
+      "siteSyncAbandonedPendingCleanup": "Sync abandoned; partial objects still need cleanup",
       "siteSyncScanProgress": "Media scan progress",
       "siteSyncFileProgress": "Synced file count",
       "siteSyncStarted": "Site-to-site sync started",
diff --git a/i18n/locales/zh-CN.json b/i18n/locales/zh-CN.json
index debd04e..a50d2f3 100644
--- a/i18n/locales/zh-CN.json
+++ b/i18n/locales/zh-CN.json
@@ -695,7 +695,9 @@
       "siteSyncResume": "继续上次同步",
       "siteSyncAbandon": "放弃并清理残留",
       "siteSyncAbandonConfirm": "确定放弃这次同步吗？将删除本次同步新建但尚未归入媒体记录的残留对象。",
+      "siteSyncAbandonWithoutTokenConfirm": "未填写目标站 Token。确定只放弃任务吗？目标站残留将标记为待清理，之后可由目标站自动清理。",
       "siteSyncAbandoned": "同步已放弃，残留对象已清理",
+      "siteSyncAbandonedPendingCleanup": "同步已放弃，残留待清理",
       "siteSyncScanProgress": "媒体扫描进度",
       "siteSyncFileProgress": "已同步文件数量",
       "siteSyncStarted": "两站点同步任务已开始",
diff --git a/server/utils/site-sync/abandon.ts b/server/utils/site-sync/abandon.ts
index 9a9ab38..8469521 100644
--- a/server/utils/site-sync/abandon.ts
+++ b/server/utils/site-sync/abandon.ts
@@ -25,29 +25,41 @@ export async function abandonSiteSyncJob(
   const targetBaseUrl = typeof job.payload.targetBaseUrl === 'string'
     ? job.payload.targetBaseUrl.replace(/\/+$/, '')
     : ''
-  let cleanup: CleanupResult
+  let cleanup: CleanupResult | null = null
+  let cleanupError: string | null = null
   if (direction === 'push') {
-    if (!targetBaseUrl || !token) {
-      throw new Error('放弃推送任务并清理目标站残留时，需要目标站 Token')
-    }
-    cleanup = await fetchSiteSyncJson<CleanupResult>(
-      `${targetBaseUrl}/api/site-sync/cleanup`,
-      token,
-      {
-        method: 'POST',
-        headers: { 'Content-Type': 'application/json' },
-        body: JSON.stringify({ jobId })
+    if (targetBaseUrl && token) {
+      try {
+        cleanup = await fetchSiteSyncJson<CleanupResult>(
+          `${targetBaseUrl}/api/site-sync/cleanup`,
+          token,
+          {
+            method: 'POST',
+            headers: { 'Content-Type': 'application/json' },
+            body: JSON.stringify({ jobId })
+          }
+        )
+      } catch (error) {
+        cleanupError = error instanceof Error ? error.message : '目标站残留清理失败'
       }
-    )
+    }
   } else {
-    cleanup = await cleanupSiteSyncJobArtifacts(jobId)
+    try {
+      cleanup = await cleanupSiteSyncJobArtifacts(jobId)
+    } catch (error) {
+      cleanupError = error instanceof Error ? error.message : '本地残留清理失败'
+    }
   }
 
-  if (cleanup.failed > 0) {
-    throw new Error(`同步残留清理失败：${cleanup.failed} 个对象`)
-  }
+  const cleanupPending = Boolean(
+    cleanupError
+    || !cleanup
+    || cleanup.failed > 0
+  )
 
-  const message = `已放弃同步 · 清理 ${cleanup.deleted} 个残留对象`
+  const message = cleanupPending
+    ? `已放弃同步 · 残留待清理${cleanupError ? `：${cleanupError}` : ''}`
+    : `已放弃同步 · 清理 ${cleanup!.deleted} 个残留对象`
   updateBackupJob(jobId, {
     status: 'failed',
     message,
@@ -58,6 +70,8 @@ export async function abandonSiteSyncJob(
       resumable: false,
       abandoned: true,
       cancelled: false,
+      cleanupPending,
+      cleanupError,
       failedKeys: [],
       cleanup
     }
diff --git a/server/utils/site-sync/runner.ts b/server/utils/site-sync/runner.ts
index 287db4a..05bcedf 100644
--- a/server/utils/site-sync/runner.ts
+++ b/server/utils/site-sync/runner.ts
@@ -1,6 +1,8 @@
 import { basename } from 'node:path'
+import { File as BufferFile } from 'node:buffer'
 import {
   Agent,
+  FormData as UndiciFormData,
   fetch as undiciFetch
 } from 'undici'
 import type { Readable } from 'node:stream'
@@ -399,7 +401,7 @@ async function uploadObject(
     getJobAbortSignal(jobId)
   )
   throwIfJobCancellationRequested(jobId)
-  const form = new FormData()
+  const form = new UndiciFormData()
   const isPrimary = key === row.key
   form.append('jobId', jobId)
   form.append('mediaKey', row.key)
@@ -412,8 +414,11 @@ async function uploadObject(
   form.append('contentType', contentType)
   form.append(
     'file',
-    new Blob([new Uint8Array(bytes)], { type: contentType }),
-    basename(key)
+    new BufferFile(
+      [new Uint8Array(bytes)],
+      basename(key),
+      { type: contentType }
+    )
   )
 
   const response = await undiciFetch(
@@ -424,7 +429,7 @@ async function uploadObject(
       headers: { 'Auth-Token': token },
       signal: getJobAbortSignal(jobId),
       dispatcher: agents.upload
-    } as Parameters<typeof undiciFetch>[1]
+    }
   )
   if (!response.ok) throw await responseError(response)
   await response.json().catch(() => null)