diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1c8870056c1..76fbbe2ef83 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -163,6 +163,7 @@ Docs: https://docs.openclaw.ai
 - Agents/failover: carry `sessionId`, `lane`, `provider`, `model`, and `profileId` attribution through `FailoverError` and `describeFailoverError`/`coerceToFailoverError` so structured error logs (e.g. `gateway.err.log` ingestion) can attribute exhausted-fallback wrapper errors to the originating session and last-attempted provider instead of dropping the metadata after the per-profile errors. Fixes #42713. (#73506) Thanks @wenxu007.
 - Context Engine: treat assembled prompt as the default authority for preemptive overflow prechecks so engines that return a windowed, self-contained context no longer trigger false hard-fail compactions on huge raw history. Engines whose assembled view can hide overflow risk can opt back into the legacy behavior with `AssembleResult.promptAuthority: "preassembly_may_overflow"`. (#74255) Thanks @100yenadmin.
 - Mattermost: refresh current native slash command registrations before accepting callbacks so stale tokens from deleted or regenerated commands stop being accepted without a gateway restart while failed validations stay briefly cached and lookup starts are rate-limited per command, gate each callback against the resolved command's own startup token so a token leaked for one slash command cannot poison another command's failure cache, redact slash validation lookup errors, and add a body read timeout to the multi-account routing path so slow callback senders cannot tie up the dispatcher. Thanks @feynman-hou and @eleqtrizit.
+- Security/dotenv: block `COMSPEC` in workspace `.env` so a malicious repo cannot redirect Windows `cmd.exe` resolution, and lock in case-insensitive workspace-`.env` regression coverage for the full Windows shell trust-root family (`COMSPEC`, `PROGRAMFILES`, `PROGRAMW6432`, `SYSTEMROOT`, `WINDIR`). (#74460) Thanks @mmaps.
 
 ## 2026.4.29
 
diff --git a/src/infra/dotenv.test.ts b/src/infra/dotenv.test.ts
index 6f0907404ac..95b2fd574a6 100644
--- a/src/infra/dotenv.test.ts
+++ b/src/infra/dotenv.test.ts
@@ -41,6 +41,19 @@ const BUNDLED_TRUST_ROOT_ENV_KEYS = BUNDLED_TRUST_ROOT_ENV_LINES.map(
   (line) => line.split("=")[0] ?? "",
 );
 
+const WINDOWS_SHELL_TRUST_ROOT_ENV_KEYS = [
+  "ComSpec",
+  "COMSPEC",
+  "ProgramFiles",
+  "PROGRAMFILES",
+  "ProgramW6432",
+  "PROGRAMW6432",
+  "SystemRoot",
+  "SYSTEMROOT",
+  "windir",
+  "WINDIR",
+] as const;
+
 async function writeEnvFile(filePath: string, contents: string) {
   await fs.mkdir(path.dirname(filePath), { recursive: true });
   await fs.writeFile(filePath, contents, "utf8");
@@ -305,6 +318,34 @@ describe("loadDotEnv", () => {
     });
   });
 
+  it("blocks Windows shell trust-root vars from workspace .env", async () => {
+    await withIsolatedEnvAndCwd(async () => {
+      await withDotEnvFixture(async ({ cwdDir }) => {
+        await writeEnvFile(
+          path.join(cwdDir, ".env"),
+          [
+            "ComSpec=.\\evil-comspec",
+            "COMSPEC=.\\evil-comspec-upper",
+            "ProgramFiles=.\\evil-pfiles",
+            "PROGRAMFILES=.\\evil-pfiles-upper",
+            "ProgramW6432=.\\evil-pw6432",
+            "PROGRAMW6432=.\\evil-pw6432-upper",
+            "SystemRoot=.\\fake-root",
+            "SYSTEMROOT=.\\fake-root-upper",
+            "windir=.\\fake-windir",
+            "WINDIR=.\\fake-windir-upper",
+          ].join("\n"),
+        );
+
+        clearEnv(WINDOWS_SHELL_TRUST_ROOT_ENV_KEYS);
+
+        loadWorkspaceDotEnvFile(path.join(cwdDir, ".env"), { quiet: true });
+
+        expectEnvUndefined(WINDOWS_SHELL_TRUST_ROOT_ENV_KEYS);
+      });
+    });
+  });
+
   it("blocks path-override vars (OPENCLAW_AGENT_DIR, OPENCLAW_BUNDLED_PLUGINS_DIR, PI_CODING_AGENT_DIR, OPENCLAW_OAUTH_DIR) from workspace .env", async () => {
     await withIsolatedEnvAndCwd(async () => {
       await withDotEnvFixture(async ({ base, cwdDir }) => {
diff --git a/src/infra/dotenv.ts b/src/infra/dotenv.ts
index 34e7eb977b9..47ae1c96bd1 100644
--- a/src/infra/dotenv.ts
+++ b/src/infra/dotenv.ts
@@ -23,6 +23,7 @@ const BLOCKED_WORKSPACE_DOTENV_KEYS = new Set([
   "CLAWHUB_TOKEN",
   "CLAWHUB_URL",
   "CLOUDSDK_PYTHON",
+  "COMSPEC",
   "HTTP_PROXY",
   "HTTPS_PROXY",
   "HOMEBREW_BREW_FILE",