fix(security): block env depth-overflow approval bypass

src/infra/exec-approvals.test.ts

@@ -299,6 +299,36 @@ describe("exec approvals command resolution", () => {
     expect(allowlistEval.segmentSatisfiedBy).toEqual([null]);
   });
 
+  it("fails closed when transparent env wrappers exceed unwrap depth", () => {
+    if (process.platform === "win32") {
+      return;
+    }
+    const dir = makeTempDir();
+    const binDir = path.join(dir, "bin");
+    fs.mkdirSync(binDir, { recursive: true });
+    const envPath = path.join(binDir, "env");
+    fs.writeFileSync(envPath, "#!/bin/sh\n");
+    fs.chmodSync(envPath, 0o755);
+
+    const analysis = analyzeArgvCommand({
+      argv: [envPath, envPath, envPath, envPath, envPath, "/bin/sh", "-c", "echo pwned"],
+      cwd: dir,
+      env: makePathEnv(binDir),
+    });
+    const allowlistEval = evaluateExecAllowlist({
+      analysis,
+      allowlist: [{ pattern: envPath }],
+      safeBins: normalizeSafeBins([]),
+      cwd: dir,
+    });
+
+    expect(analysis.ok).toBe(true);
+    expect(analysis.segments[0]?.resolution?.policyBlocked).toBe(true);
+    expect(analysis.segments[0]?.resolution?.blockedWrapper).toBe("env");
+    expect(allowlistEval.allowlistSatisfied).toBe(false);
+    expect(allowlistEval.segmentSatisfiedBy).toEqual([null]);
+  });
+
   it("unwraps env wrapper with shell inner executable", () => {
     const resolution = resolveCommandResolutionFromArgv(["/usr/bin/env", "bash", "-lc", "echo hi"]);
     expect(resolution?.rawExecutable).toBe("bash");

src/infra/exec-wrapper-resolution.ts

@@ -478,6 +478,17 @@ export function resolveDispatchWrapperExecutionPlan(
     }
     current = unwrap.argv;
   }
+  if (wrappers.length >= maxDepth) {
+    const overflow = unwrapKnownDispatchWrapperInvocation(current);
+    if (overflow.kind === "blocked" || overflow.kind === "unwrapped") {
+      return {
+        argv: current,
+        wrappers,
+        policyBlocked: true,
+        blockedWrapper: overflow.wrapper,
+      };
+    }
+  }
   return { argv: current, wrappers, policyBlocked: false };
 }
 

src/node-host/invoke-system-run.test.ts

@@ -348,4 +348,99 @@ describe("handleSystemRunInvoke mac app exec host routing", () => {
       }),
     );
   });
+
+  it("denies nested env shell payloads when wrapper depth is exceeded", async () => {
+    if (process.platform === "win32") {
+      return;
+    }
+    const tempHome = fs.mkdtempSync(path.join(os.tmpdir(), "openclaw-env-depth-overflow-"));
+    const previousOpenClawHome = process.env.OPENCLAW_HOME;
+    const marker = path.join(tempHome, "pwned.txt");
+    process.env.OPENCLAW_HOME = tempHome;
+    saveExecApprovals({
+      version: 1,
+      defaults: {
+        security: "allowlist",
+        ask: "on-miss",
+        askFallback: "deny",
+      },
+      agents: {
+        main: {
+          allowlist: [{ pattern: "/usr/bin/env" }],
+        },
+      },
+    });
+    const runCommand = vi.fn(async () => {
+      fs.writeFileSync(marker, "executed");
+      return {
+        success: true,
+        stdout: "local-ok",
+        stderr: "",
+        timedOut: false,
+        truncated: false,
+        exitCode: 0,
+        error: null,
+      };
+    });
+    const sendInvokeResult = vi.fn(async () => {});
+    const sendNodeEvent = vi.fn(async () => {});
+
+    try {
+      await handleSystemRunInvoke({
+        client: {} as never,
+        params: {
+          command: [
+            "/usr/bin/env",
+            "/usr/bin/env",
+            "/usr/bin/env",
+            "/usr/bin/env",
+            "/usr/bin/env",
+            "/bin/sh",
+            "-c",
+            `echo PWNED > ${marker}`,
+          ],
+          sessionKey: "agent:main:main",
+        },
+        skillBins: {
+          current: async () => [],
+        },
+        execHostEnforced: false,
+        execHostFallbackAllowed: true,
+        resolveExecSecurity: () => "allowlist",
+        resolveExecAsk: () => "on-miss",
+        isCmdExeInvocation: () => false,
+        sanitizeEnv: () => undefined,
+        runCommand,
+        runViaMacAppExecHost: vi.fn(async () => null),
+        sendNodeEvent,
+        buildExecEventPayload: (payload) => payload,
+        sendInvokeResult,
+        sendExecFinishedEvent: vi.fn(async () => {}),
+        preferMacAppExecHost: false,
+      });
+    } finally {
+      if (previousOpenClawHome === undefined) {
+        delete process.env.OPENCLAW_HOME;
+      } else {
+        process.env.OPENCLAW_HOME = previousOpenClawHome;
+      }
+      fs.rmSync(tempHome, { recursive: true, force: true });
+    }
+
+    expect(runCommand).not.toHaveBeenCalled();
+    expect(fs.existsSync(marker)).toBe(false);
+    expect(sendNodeEvent).toHaveBeenCalledWith(
+      expect.anything(),
+      "exec.denied",
+      expect.objectContaining({ reason: "approval-required" }),
+    );
+    expect(sendInvokeResult).toHaveBeenCalledWith(
+      expect.objectContaining({
+        ok: false,
+        error: expect.objectContaining({
+          message: "SYSTEM_RUN_DENIED: approval required",
+        }),
+      }),
+    );
+  });
 });