diff --git a/apps/server/src/sandbox/client.ts b/apps/server/src/sandbox/client.ts
index 37c72d3b..9a06ea42 100644
--- a/apps/server/src/sandbox/client.ts
+++ b/apps/server/src/sandbox/client.ts
@@ -51,6 +51,15 @@ function command(memoryMb: number): { cmd: string; args: string[] } {
   return { cmd: exe, args: ["--role", "sandbox"] };
 }
 
+/**
+ * 子进程环境:清空,只留 PATH。编译产物启动时要按 PATH 解析 --allow-run 里的命令名(ffprobe、cat…),
+ * 没有 PATH 会在进程入口报「no path to search」直接退出,所有沙箱任务都失败(2026-10 Bangumi 热门、字幕验证码即此)。
+ * 子进程随后撤销全部权限,PATH 不放大能力。
+ */
+export function sandboxEnv(): Record<string, string> {
+  return { PATH: Deno.env.get("PATH") || "/usr/local/bin:/usr/bin:/bin" };
+}
+
 /** 子进程实际内存(KB);读不到返回 null */
 async function rssKb(pid: number): Promise<number | null> {
   const s = await readProcText(`/proc/${pid}/status`);
@@ -75,7 +84,7 @@ export async function runSandbox<J extends SandboxJobName>(
       stdin: "piped",
       stdout: "piped",
       stderr: "piped",
-      env: {},
+      env: sandboxEnv(),
       clearEnv: true,
     }).spawn();
   } catch (e) {
diff --git a/apps/server/test/sandbox/sandbox.test.ts b/apps/server/test/sandbox/sandbox.test.ts
index ff37d4b7..370845d5 100644
--- a/apps/server/test/sandbox/sandbox.test.ts
+++ b/apps/server/test/sandbox/sandbox.test.ts
@@ -1,13 +1,19 @@
 import { buildFakeTorrent, RAR5_SAMPLE_BASE64, SEVENZIP_SUBTITLE_BASE64, ZIMUKU_CAPTCHA } from "@umt/testkit";
 import { zipSync } from "fflate";
 import { describe, expect, it } from "vitest";
-import { runSandbox, SandboxError } from "../../src/sandbox/client.ts";
+import { runSandbox, SandboxError, sandboxEnv } from "../../src/sandbox/client.ts";
 import { b64encode } from "../../src/sandbox/jobs.ts";
 
 // 沙箱(docs/adr/ADR-005-sandbox.md):子进程撤销全部权限;卡死超时强杀;内存超限强杀;任务错误原样带回
 const enc = (s: string) => new TextEncoder().encode(s);
 
 describe("沙箱子进程", () => {
+  it("子进程环境只带 PATH(编译产物入口要按 PATH 解析 --allow-run 的命令名,没有会直接退出)", () => {
+    const env = sandboxEnv();
+    expect(Object.keys(env)).toEqual(["PATH"]);
+    expect(env.PATH).toBeTruthy();
+  });
+
   it("正常返回;子进程里读文件被拒绝", async () => {
     expect(await runSandbox("self.test", { mode: "ok" })).toEqual({ ok: true });
     await expect(runSandbox("self.test", { mode: "io" })).rejects.toMatchObject({ kind: "job", message: /NotCapable/ });
diff --git a/scripts/check-compiled-binary.sh b/scripts/check-compiled-binary.sh
index bf9ad7b1..07d6651b 100755
--- a/scripts/check-compiled-binary.sh
+++ b/scripts/check-compiled-binary.sh
@@ -10,8 +10,16 @@ case "$bin" in /*) ;; *) bin="$PWD/$bin" ;; esac
 out=$(cd /tmp && env -i PATH="$PATH" "$bin" --role preflight 2>&1)
 code=$?
 if [ "$code" -eq 2 ] && printf '%s' "$out" | grep -q '配置无效'; then
-  echo "check-compiled-binary: ok(模块图加载完整)"
-  exit 0
+  # 沙箱子进程:与 sandbox/client.ts 同样的环境(只有 PATH)拉起 `--role sandbox`,请求一个不存在的任务,
+  # 应回一行 {"ok":false,...};入口就崩(如 --allow-run 解析失败)会没有这行
+  sb=$(cd /tmp && printf '{"job":"__check__","input":null}' | env -i PATH="$PATH" "$bin" --role sandbox 2>&1)
+  if printf '%s' "$sb" | grep -q '"ok":false'; then
+    echo "check-compiled-binary: ok(模块图加载完整,沙箱子进程能启动)"
+    exit 0
+  fi
+  echo "check-compiled-binary: 沙箱子进程起不来:" >&2
+  printf '%s\n' "$sb" >&2
+  exit 1
 fi
 echo "check-compiled-binary: 编译产物自检失败(退出码 $code):" >&2
 printf '%s\n' "$out" >&2