diff --git a/app/task/MAA/tools/avd.py b/app/task/MAA/tools/avd.py
index f4244ec0d1..5a8d67603f 100644
--- a/app/task/MAA/tools/avd.py
+++ b/app/task/MAA/tools/avd.py
@@ -50,6 +50,7 @@
 from __future__ import annotations
 
 import hashlib
+import json
 import shutil
 from pathlib import Path
 from typing import Any
@@ -82,13 +83,36 @@ def _sha256(path: Path) -> str:
     return hashlib.sha256(path.read_bytes()).hexdigest()
 
 
+#: ``modavd-manifest.json`` 里外壳的路径。ModAVD 0.40.1 起整包自带外壳，就在这里。
+PACKAGE_SHIM_PATH = f"{MUMU_SHIM_DIR}/shell/sdk/external_renderer_ipc.dll"
+
+
+def _package_ships_shim(root: str | Path) -> bool:
+    """根目录的 ``modavd-manifest.json`` 列了外壳：这份文件归 ModAVD 的包管。"""
+    try:
+        manifest = json.loads(
+            (Path(root) / "modavd-manifest.json").read_text(encoding="utf-8-sig")
+        )
+    except (OSError, ValueError):
+        return False
+    files = manifest.get("files") if isinstance(manifest, dict) else None
+    return isinstance(files, dict) and PACKAGE_SHIM_PATH in files
+
+
 def ensure_mumu_shim(root: str | Path) -> Path:
-    """确保 ``<根>\\mumu-shim\\shell\\sdk\\external_renderer_ipc.dll`` 是随本体发的那一份。
+    """确保 ``<根>\\mumu-shim\\shell\\sdk\\external_renderer_ipc.dll`` 在，MAA 能当 MuMu 载入。
+
+    ModAVD 0.40.1 起整包自带这份外壳（列在 ``modavd-manifest.json`` 里），这时用包里的，
+    不覆盖：换成本体的那份会和包的清单对不上，ModAVD 用 Mirror 酱增量更新时就核对失败。
+    包里的被删了才补本体这份，下次 ModAVD 更新会换回包里的。
 
-    随本体更新 DLL 也会变，所以不只看在不在，内容不同就覆盖。正在被 MAA 加载时覆盖会失败，
-    那就留着旧的并记警告——旧的也能用，下次运行前再换。
+    更早的包不带外壳，照旧放本体发的那一份：随本体更新 DLL 也会变，所以不只看在不在，
+    内容不同就覆盖。正在被 MAA 加载时覆盖会失败，那就留着旧的并记警告——旧的也能用，
+    下次运行前再换。
     """
     target = shim_dll(root)
+    if target.is_file() and _package_ships_shim(root):
+        return target
     if not SHIM_SOURCE.is_file():
         raise FileNotFoundError(f"缺少截图组件 {SHIM_SOURCE}")
     if target.is_file() and _sha256(target) == _sha256(SHIM_SOURCE):
diff --git a/changelog.d/fix-avd-shim-package-owned-20261113.fix.md b/changelog.d/fix-avd-shim-package-owned-20261113.fix.md
new file mode 100644
index 0000000000..75b80bf26a
--- /dev/null
+++ b/changelog.d/fix-avd-shim-package-owned-20261113.fix.md
@@ -0,0 +1,2 @@
+project: maa
+ModAVD 自带 MAA 截图外壳时不再覆盖，免得它的增量更新核对失败
diff --git a/tests/task/test_maa_avd_shim.py b/tests/task/test_maa_avd_shim.py
new file mode 100644
index 0000000000..d17123da3b
--- /dev/null
+++ b/tests/task/test_maa_avd_shim.py
@@ -0,0 +1,76 @@
+"""MAA 截图外壳的放置：ModAVD 包自带外壳时不覆盖。"""
+
+from __future__ import annotations
+
+import json
+from pathlib import Path
+
+import pytest
+
+from app.task.MAA.tools import avd
+
+
+@pytest.fixture
+def own_shim(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> bytes:
+    src = tmp_path / "res" / "external_renderer_ipc.dll"
+    src.parent.mkdir(parents=True)
+    src.write_bytes(b"auto-mas shim")
+    monkeypatch.setattr(avd, "SHIM_SOURCE", src)
+    return b"auto-mas shim"
+
+
+def _root(tmp_path: Path, *, shim: bytes | None, listed: bool | None) -> Path:
+    root = tmp_path / "root"
+    root.mkdir()
+    if shim is not None:
+        avd.shim_dll(root).parent.mkdir(parents=True)
+        avd.shim_dll(root).write_bytes(shim)
+    if listed is not None:
+        files = {"tools/modavd.exe": {"size": 1, "sha256": "0" * 64}}
+        if listed:
+            files[avd.PACKAGE_SHIM_PATH] = {"size": 12, "sha256": "1" * 64}
+        (root / "modavd-manifest.json").write_text(
+            json.dumps({"schema": 1, "version": "v0.40.1", "files": files}),
+            encoding="utf-8",
+        )
+    return root
+
+
+def test_package_shim_is_left_alone(tmp_path: Path, own_shim: bytes) -> None:
+    root = _root(tmp_path, shim=b"package shim", listed=True)
+    assert avd.ensure_mumu_shim(root) == avd.shim_dll(root)
+    assert avd.shim_dll(root).read_bytes() == b"package shim"
+
+
+def test_package_shim_missing_gets_ours(tmp_path: Path, own_shim: bytes) -> None:
+    root = _root(tmp_path, shim=None, listed=True)
+    avd.ensure_mumu_shim(root)
+    assert avd.shim_dll(root).read_bytes() == own_shim
+
+
+@pytest.mark.parametrize("listed", [False, None])
+def test_older_package_gets_ours(
+    tmp_path: Path, own_shim: bytes, listed: bool | None
+) -> None:
+    """0.40.1 以前的包不带外壳（清单里没有，或者没有清单）：照旧换成本体的那份。"""
+    root = _root(tmp_path, shim=b"old copy", listed=listed)
+    avd.ensure_mumu_shim(root)
+    assert avd.shim_dll(root).read_bytes() == own_shim
+
+
+@pytest.mark.parametrize("text", ["{", "[]", '{"files": []}', "{}"])
+def test_unreadable_manifest_counts_as_older(
+    tmp_path: Path, own_shim: bytes, text: str
+) -> None:
+    root = _root(tmp_path, shim=b"old copy", listed=None)
+    (root / "modavd-manifest.json").write_text(text, encoding="utf-8")
+    avd.ensure_mumu_shim(root)
+    assert avd.shim_dll(root).read_bytes() == own_shim
+
+
+def test_bom_manifest_is_read(tmp_path: Path, own_shim: bytes) -> None:
+    root = _root(tmp_path, shim=b"package shim", listed=True)
+    path = root / "modavd-manifest.json"
+    path.write_bytes(b"\xef\xbb\xbf" + path.read_bytes())
+    avd.ensure_mumu_shim(root)
+    assert avd.shim_dll(root).read_bytes() == b"package shim"