diff --git a/app/lib/cart-edit.js b/app/lib/cart-edit.js
index fc3eba0..bf338a2 100644
--- a/app/lib/cart-edit.js
+++ b/app/lib/cart-edit.js
@@ -17,8 +17,14 @@ function e(e, t = {}) {
 function t(e) {
   return JSON.parse(JSON.stringify(e));
 }
-function n(n) {
-  return n.map((n) => t(e(n)));
+// 版本只接受服务端对规范购物车生成的 SHA-256，缺失时停止位置写入。
+function requireCartRevision(cart) {
+  if (
+    typeof cart?.revision !== `string` ||
+    !/^[a-f0-9]{64}$/.test(cart.revision)
+  )
+    throw Error(`购物车版本缺失，请返回购物车刷新后重试`);
+  return cart.revision;
 }
 // 递归排序对象键并省略 undefined，使相同内容不受属性插入顺序影响。
 function r(e) {
@@ -76,11 +82,12 @@ async function l(e) {
   });
 }
 /**
- * n 为 API 客户端，r 包含 position/item；返回函数的第二参 u 检查报价是否仍有效。
- * 保存前重取购物车并比较原始项，提交 expected_item 供后端进一步检测并发变更。
+ * n 为 API 客户端，r 包含首次读取时绑定的 position/item/revision；第二参 u 检查报价是否仍有效。
+ * 保存始终提交原始版本；冲突必须返回购物车重新确认，不能用新版本授权旧位置。
  */
 function u(n, r) {
   let a = r ? t(r.item) : null,
+    revision = r ? requireCartRevision(r) : null,
     c = !1;
   return async (l, u) => {
     if (!r || !a) throw Error(`购物车编辑上下文缺失`);
@@ -88,13 +95,10 @@ function u(n, r) {
     c = !0;
     let d = t(e(a, l));
     try {
-      let c = (await n.get(`/cart`)).list?.[r.position];
-      if (!c || i(c) !== i(a))
-        throw Error(`购物车商品已变化，请返回购物车刷新后重新编辑`);
       if (!u()) throw Error(`配置已改变，请重新确认报价后保存`);
       let l = await n.put(`/cart/${r.position}`, {
           ...d,
-          expected_item: e(a),
+          expected_revision: revision,
         }),
         f = a;
       a = t({
@@ -109,9 +113,15 @@ function u(n, r) {
           (p.fingerprints[r.position] = await s(a)),
         l
       );
+    } catch (error) {
+      if ([409, 428].includes(Number(error?.status)))
+        throw Error(`购物车状态已变化，请返回购物车刷新并重新确认配置`, {
+          cause: error,
+        });
+      throw error;
     } finally {
       c = !1;
     }
   };
 }
-export { l as a, c as i, t as n, a as o, u as r, n as t };
+export { l as a, c as i, t as n, a as o, u as r, requireCartRevision };
diff --git a/app/pages/cart/index.vue b/app/pages/cart/index.vue
index 2851c34..2da0254 100644
--- a/app/pages/cart/index.vue
+++ b/app/pages/cart/index.vue
@@ -1,6 +1,6 @@
 <script>
 /**
- * 购物车：读取服务端购物车、逐项重新报价、保留选择并结算。修改使用 revision 或 expected_cart 进行并发校验，不能把列表下标当作永久商品标识。
+ * 购物车：读取服务端购物车、逐项重新报价、保留选择并结算。位置写入必须携带同次读取的 revision，不能把列表下标当作永久商品标识。
  */
 import "~/assets/styles/PaymentDialog.BNFKQF1U.css";
 import "~/assets/styles/cart.CSS2vTmS.css";
@@ -42,7 +42,7 @@ import { t as configuration_display_t } from "~/lib/configuration-display.js";
 import { t as purchase_limit_state_t } from "~/lib/purchase-limit-state.js";
 import { a as cart_edit_a } from "~/lib/cart-edit.js";
 import { i as cart_edit_i } from "~/lib/cart-edit.js";
-import { t as cart_edit_t } from "~/lib/cart-edit.js";
+import { requireCartRevision } from "~/lib/cart-edit.js";
 // 只接受普通对象形状的数据，供配置摘要解析使用。
 function E(e) {
   return typeof e == `object` && e && !Array.isArray(e) ? e : void 0;
@@ -387,14 +387,7 @@ var me = {
           G = !1,
           K = new Map(),
           q = () => JSON.stringify(D.value),
-          J = () =>
-            O.value
-              ? {
-                  expected_revision: O.value,
-                }
-              : {
-                  expected_cart: cart_edit_t(D.value),
-                },
+          J = () => ({ expected_revision: O.value }),
           Y = (e) =>
             JSON.stringify([
               e.product_id,
@@ -524,11 +517,7 @@ var me = {
             if (G || t !== W) return;
             if (
               ((D.value = i.list ?? []),
-              (O.value =
-                typeof i.revision == `string` &&
-                /^[a-f0-9]{64}$/.test(i.revision)
-                  ? i.revision
-                  : ``),
+              (O.value = requireCartRevision(i)),
               (z.value = Object.fromEntries(
                 D.value.flatMap((e, t) => {
                   let n = r.get(Y(e));
@@ -563,15 +552,17 @@ var me = {
           let t = A.value.indexOf(e);
           t === -1 ? A.value.push(e) : A.value.splice(t, 1);
         }
-        // 遇到 409 并发冲突时重载购物车并清空选择，要求用户重新确认，避免误改已移动的下标。
+        // 并发冲突或版本缺失时重载列表并清空选择，只在重新确认后允许用户再提交。
         async function Q(e, t) {
           let n = e instanceof Error ? e.message : t;
-          e && typeof e == `object` && `status` in e && e.status === 409
+          e && typeof e == `object` && [409, 428].includes(Number(e.status))
             ? (($.value = null),
               (A.value = []),
               await Z(),
               (A.value = []),
-              (M.value = N.value ? `${n}；${M.value}` : n))
+              (M.value = N.value
+                ? `${n}；${M.value}`
+                : `${n}；请重新选择商品并确认后再提交`))
             : (M.value = n);
         }
         // 先保存购物车编辑上下文，再进入对应商品页；商品页会再次确认该位置仍匹配商品。
diff --git a/app/pages/products/[id].vue b/app/pages/products/[id].vue
index 12d46ba..c0fa689 100644
--- a/app/pages/products/[id].vue
+++ b/app/pages/products/[id].vue
@@ -50,6 +50,7 @@ import PaymentDialog from "~/components/PaymentDialog.vue";
 import { t as product_order_module_t } from "~/lib/product-order-module.js";
 import ConfigLoadingShell from "~/components/config/ConfigLoadingShell.vue";
 import { n as cart_edit_n } from "~/lib/cart-edit.js";
+import { requireCartRevision } from "~/lib/cart-edit.js";
 import CommonConfig from "~/components/config/CommonConfig.vue";
 import FinanceConfig from "~/components/config/FinanceConfig.vue";
 import JyCloudConfig from "~/components/config/JyCloudConfig.vue";
@@ -119,7 +120,8 @@ var j = {
             if (K.value !== null && U.value)
               return {
                 position: K.value,
-                item: U.value,
+                item: U.value.item,
+                revision: U.value.revision,
               };
             return undefined;
           }),
@@ -150,11 +152,15 @@ var j = {
             if (r.order_allowed === !1)
               throw Error(r.order_block_reason || `该产品已停止订购`);
             if (K.value !== null) {
-              let t = (await L.get(`/cart`))?.list?.[K.value];
-              if (!t || Number(t.product_id) !== Number(R))
+              let t = await L.get(`/cart`),
+                item = t?.list?.[K.value];
+              if (!item || Number(item.product_id) !== Number(R))
                 throw Error(`购物车商品已变化，请返回购物车重新编辑`);
               if (e !== Z) return;
-              U.value = cart_edit_n(t);
+              U.value = {
+                item: cart_edit_n(item),
+                revision: requireCartRevision(t),
+              };
             }
             let i = await product_order_module_t(L, r);
             if (e !== Z) return;
diff --git a/tests/review-purchase.e2e.test.mjs b/tests/review-purchase.e2e.test.mjs
index 5586195..58c7fa3 100644
--- a/tests/review-purchase.e2e.test.mjs
+++ b/tests/review-purchase.e2e.test.mjs
@@ -1,5 +1,6 @@
 /** 购买回归走真实配置页、实例动作和支付界面；只替换已配置后端的 HTTP 响应。 */
 import assert from "node:assert/strict";
+import { createHash } from "node:crypto";
 import test from "node:test";
 import {
   appOrigin,
@@ -10,7 +11,10 @@ import {
   scenario,
 } from "./helpers/console-browser.mjs";
 
-async function purchaseBoundary(page, { savedCascade } = {}) {
+async function purchaseBoundary(
+  page,
+  { savedCascade, missingCartRevision = false, rejectCartWrites = 0 } = {},
+) {
   const state = {
     authorized: false,
     orders: new Map(),
@@ -19,7 +23,29 @@ async function purchaseBoundary(page, { savedCascade } = {}) {
     carts: [],
     settlements: [],
     requests: [],
+    cartReads: 0,
+    cartRevisions: [],
+    cartWrites: [],
+    cartRows:
+      savedCascade === undefined
+        ? []
+        : [
+            {
+              product_id: 123,
+              qty: 1,
+              config_options: {
+                cycle: "free",
+                cascade_configoption: {
+                  5: { item_id: savedCascade, quantity: 1 },
+                },
+              },
+              customfield: {},
+              self_defined_field: {},
+            },
+          ],
   };
+  const revision = () =>
+    createHash("sha256").update(JSON.stringify(state.cartRows)).digest("hex");
   const tree = [
     {
       item_name: "隐藏区域",
@@ -179,26 +205,44 @@ async function purchaseBoundary(page, { savedCascade } = {}) {
         state.carts.push(body);
         return respond({});
       }
-      if (path === "/cart" && method === "GET")
+      if (path === "/cart" && method === "GET") {
+        state.cartReads++;
+        state.cartRevisions.push(revision());
         return respond({
-          list:
-            savedCascade === undefined
-              ? []
-              : [
-                  {
-                    product_id: 123,
-                    qty: 1,
-                    config_options: {
-                      cycle: "free",
-                      cascade_configoption: {
-                        5: { item_id: savedCascade, quantity: 1 },
-                      },
-                    },
-                    customfield: {},
-                    self_defined_field: {},
-                  },
-                ],
+          list: state.cartRows.map((row) => ({ ...row, name: "本地级联配置" })),
+          ...(missingCartRevision ? {} : { revision: revision() }),
         });
+      }
+      if (method === "PUT" && /^\/cart\/\d+(\/qty)?$/.test(path)) {
+        const currentRevision = revision();
+        state.cartWrites.push({
+          method,
+          path,
+          body,
+          cartReads: state.cartReads,
+          revision: currentRevision,
+        });
+        const status =
+          rejectCartWrites ||
+          (!body?.expected_revision
+            ? 428
+            : body.expected_revision !== currentRevision
+              ? 409
+              : 200);
+        if (status !== 200)
+          return respond({}, { status, msg: "购物车状态待重新确认" });
+        const position = Number(path.split("/")[2]);
+        state.cartRows[position] = path.endsWith("/qty")
+          ? { ...state.cartRows[position], qty: body.qty }
+          : {
+              product_id: body.product_id,
+              qty: body.qty,
+              config_options: body.config_options,
+              customfield: body.customfield,
+              self_defined_field: body.self_defined_field,
+            };
+        return respond({ revision: revision() });
+      }
       if (path === "/product/settle") {
         state.settlements.push(body);
         return respond({ order_id: 42, amount: "0.00" });
@@ -440,3 +484,175 @@ test(
     });
   },
 );
+
+test(
+  "cart configuration keeps the original revision without fetching a replacement before saving",
+  { timeout: 30000 },
+  (t) =>
+    scenario(t, {}, async (page) => {
+      const state = await purchaseBoundary(page, { savedCascade: 20 });
+      await login(page, "/products/123?edit_position=0");
+      const save = page.getByRole("button", { name: "保存配置", exact: true });
+      await eventually(
+        () => save.isEnabled(),
+        Boolean,
+        "编辑配置必须先取得有效报价",
+      );
+      await save.click();
+      await eventually(
+        () => state.cartWrites.length,
+        (count) => count === 1,
+        "配置只能提交一次",
+      );
+      const write = state.cartWrites[0];
+      assert.equal(write.body.expected_revision, write.revision);
+      assert.equal(write.cartReads, 1);
+      assert.equal(Object.hasOwn(write.body, "expected_item"), false);
+      assert.equal(Object.hasOwn(write.body, "expected_cart"), false);
+      await page.waitForURL((url) => url.pathname === "/cart");
+      return {
+        originalRevisionSubmitted: true,
+        readsBeforeSave: write.cartReads,
+        configurationWrites: 1,
+      };
+    }),
+);
+
+for (const status of [409, 428]) {
+  test(
+    `cart editing stops after server ${status} and requires returning to the cart`,
+    { timeout: 30000 },
+    (t) =>
+      scenario(t, {}, async (page) => {
+        const state = await purchaseBoundary(page, {
+          savedCascade: 20,
+          rejectCartWrites: status === 428 ? status : 0,
+        });
+        await login(page, "/products/123?edit_position=0");
+        const save = page.getByRole("button", {
+          name: "保存配置",
+          exact: true,
+        });
+        await eventually(
+          () => save.isEnabled(),
+          Boolean,
+          "编辑配置必须先取得有效报价",
+        );
+        const originalRevision = state.cartRevisions[0];
+        // 另一会话只改动兄弟项，当前商品仍相同，也不能把新版本套在旧位置上。
+        if (status === 409)
+          state.cartRows.push({ ...state.cartRows[0], qty: 2 });
+        await save.click();
+        await eventually(
+          () => state.cartWrites.length,
+          (count) => count === 1,
+          "冲突只允许一次写入尝试",
+        );
+        await page.locator(".p-message-error").waitFor();
+        assert.equal(new URL(page.url()).pathname, "/products/123");
+        assert.equal(state.cartReads, 1);
+        assert.equal(
+          state.cartWrites[0].body.expected_revision,
+          originalRevision,
+        );
+        if (status === 409)
+          assert.notEqual(state.cartWrites[0].revision, originalRevision);
+        await page
+          .locator(".product-links")
+          .getByRole("link", { name: "购物车", exact: true })
+          .click();
+        await page.waitForURL((url) => url.pathname === "/cart");
+        await eventually(
+          () => state.cartReads,
+          (count) => count === 2,
+          "返回购物车后重新读取可确认的列表",
+        );
+        assert.equal(state.cartWrites.length, 1);
+        return {
+          rejectedStatus: status,
+          configurationWrites: 1,
+          readsOnlyAfterReturning: 2,
+        };
+      }),
+  );
+
+  test(
+    `cart server ${status} clears the selection without retrying a positional mutation`,
+    { timeout: 30000 },
+    (t) =>
+      scenario(t, {}, async (page) => {
+        const state = await purchaseBoundary(page, {
+          savedCascade: 20,
+          rejectCartWrites: status,
+        });
+        await login(page, "/cart");
+        const selected = page.getByRole("checkbox", {
+          name: "选择 本地级联配置",
+          exact: true,
+        });
+        await selected.waitFor();
+        assert.equal(await selected.isChecked(), true);
+        await page
+          .getByRole("button", {
+            name: "增加 本地级联配置 的数量",
+            exact: true,
+          })
+          .click();
+        await eventually(
+          () => state.cartWrites.length,
+          (count) => count === 1,
+          "修改数量只提交一次",
+        );
+        await eventually(
+          () => selected.isChecked(),
+          (checked) => !checked,
+          "冲突后必须重新选择商品确认",
+        );
+        assert.equal(
+          state.cartWrites[0].body.expected_revision,
+          state.cartWrites[0].revision,
+        );
+        assert.equal(
+          Object.hasOwn(state.cartWrites[0].body, "expected_cart"),
+          false,
+        );
+        assert.equal(
+          await page
+            .getByRole("button", { name: "提交订单", exact: true })
+            .isDisabled(),
+          true,
+        );
+        assert.equal(state.cartWrites.length, 1);
+        return {
+          rejectedStatus: status,
+          mutationAttempts: 1,
+          selectionCleared: true,
+        };
+      }),
+  );
+}
+
+test(
+  "a cart response without a revision offers reload and cannot mutate old positions",
+  { timeout: 30000 },
+  (t) =>
+    scenario(t, {}, async (page) => {
+      const state = await purchaseBoundary(page, {
+        savedCascade: 20,
+        missingCartRevision: true,
+      });
+      await login(page, "/cart");
+      await page
+        .getByRole("button", { name: "重新加载", exact: true })
+        .waitFor();
+      assert.equal(await page.locator(".cart-item").count(), 0);
+      assert.equal(
+        await page
+          .getByRole("button", { name: "提交订单", exact: true })
+          .count(),
+        0,
+      );
+      assert.equal(state.cartWrites.length, 0);
+      return { missingRevisionBlocked: true, mutationAttempts: 0 };
+    }),
+);
diff --git a/tests/review-style-layout.e2e.test.mjs b/tests/review-style-layout.e2e.test.mjs
index ca12d1c..fd4652d 100644
--- a/tests/review-style-layout.e2e.test.mjs
+++ b/tests/review-style-layout.e2e.test.mjs
@@ -3,6 +3,7 @@
  * 所有内容来自生产已有的本地 HTTP 边界；尺寸断言读取实际 DOM，不检查源码形状。
  */
 import assert from "node:assert/strict";
+import { createHash } from "node:crypto";
 import { test } from "node:test";
 import { firefox } from "playwright";
 import {
@@ -118,17 +119,22 @@ async function layoutBoundary(
             create_time: 1700000000,
           },
         });
-      if (path === "/cart")
+      if (path === "/cart") {
+        const list = Array.from({ length: 14 }, (_, index) => ({
+          product_id: 123,
+          qty: 1,
+          name: `云产品 ${index + 1}`,
+          config_options: { cpu: index + 1 },
+          customfield: {},
+          self_defined_field: {},
+        }));
         return reply({
-          list: Array.from({ length: 14 }, (_, index) => ({
-            product_id: 123,
-            qty: 1,
-            name: `云产品 ${index + 1}`,
-            config_options: { cpu: index + 1 },
-            customfield: {},
-            self_defined_field: {},
-          })),
+          list,
+          revision: createHash("sha256")
+            .update(JSON.stringify(list))
+            .digest("hex"),
         });
+      }
       if (path === "/product/123/config_option")
         return reply({
           price_total: "10.00",