From c23ad91a145dbf2f2ff9e68a4e7b31a706f80965 Mon Sep 17 00:00:00 2001
From: Peter Steinberger <steipete@gmail.com>
Date: Thu, 23 Apr 2026 07:09:34 +0100
Subject: [PATCH] fix(matrix): keep DM allowlist out of room commands

---
 .../src/matrix/monitor/access-state.test.ts   | 20 +++++++++-
 .../matrix/src/matrix/monitor/access-state.ts |  2 +-
 .../matrix/src/matrix/monitor/handler.test.ts | 39 +++++++++++++++++++
 3 files changed, 59 insertions(+), 2 deletions(-)

diff --git a/extensions/matrix/src/matrix/monitor/access-state.test.ts b/extensions/matrix/src/matrix/monitor/access-state.test.ts
index b51e45d2e9b..f938e97a1b8 100644
--- a/extensions/matrix/src/matrix/monitor/access-state.test.ts
+++ b/extensions/matrix/src/matrix/monitor/access-state.test.ts
@@ -22,7 +22,7 @@ describe("resolveMatrixMonitorAccessState", () => {
     expect(state.roomUserMatch?.allowed).toBe(true);
     expect(state.groupAllowMatch?.allowed).toBe(false);
     expect(state.commandAuthorizers).toEqual([
-      { configured: true, allowed: false },
+      { configured: false, allowed: false },
       { configured: true, allowed: true },
       { configured: true, allowed: false },
     ]);
@@ -47,6 +47,24 @@ describe("resolveMatrixMonitorAccessState", () => {
     ]);
   });
 
+  it("does not let configured DM allowFrom authorize room control commands", () => {
+    const state = resolveMatrixMonitorAccessState({
+      allowFrom: ["@owner:example.org"],
+      storeAllowFrom: [],
+      groupAllowFrom: ["@admin:example.org"],
+      roomUsers: [],
+      senderId: "@owner:example.org",
+      isRoom: true,
+    });
+
+    expect(state.directAllowMatch.allowed).toBe(true);
+    expect(state.commandAuthorizers).toEqual([
+      { configured: false, allowed: false },
+      { configured: false, allowed: false },
+      { configured: true, allowed: false },
+    ]);
+  });
+
   it("keeps room-user matching disabled for dm traffic", () => {
     const state = resolveMatrixMonitorAccessState({
       allowFrom: [],
diff --git a/extensions/matrix/src/matrix/monitor/access-state.ts b/extensions/matrix/src/matrix/monitor/access-state.ts
index 586319420a9..0733778de96 100644
--- a/extensions/matrix/src/matrix/monitor/access-state.ts
+++ b/extensions/matrix/src/matrix/monitor/access-state.ts
@@ -37,7 +37,7 @@ export function resolveMatrixMonitorAccessState(params: {
   ]);
   const effectiveGroupAllowFrom = normalizeMatrixAllowList(params.groupAllowFrom);
   const effectiveRoomUsers = normalizeMatrixAllowList(params.roomUsers);
-  const commandAllowFrom = params.isRoom ? configuredAllowFrom : effectiveAllowFrom;
+  const commandAllowFrom = params.isRoom ? [] : effectiveAllowFrom;
 
   const directAllowMatch = resolveMatrixAllowListMatch({
     allowList: effectiveAllowFrom,
diff --git a/extensions/matrix/src/matrix/monitor/handler.test.ts b/extensions/matrix/src/matrix/monitor/handler.test.ts
index b46b6ed60a4..1c6d0ba245f 100644
--- a/extensions/matrix/src/matrix/monitor/handler.test.ts
+++ b/extensions/matrix/src/matrix/monitor/handler.test.ts
@@ -512,6 +512,45 @@ describe("matrix monitor handler pairing account scope", () => {
     expect(readAllowFromStore).not.toHaveBeenCalled();
   });
 
+  it("blocks room control commands from configured DM-only senders", async () => {
+    const hasControlCommand = vi.fn((text?: string) => text === "/new");
+    const { handler, finalizeInboundContext, recordInboundSession } =
+      createMatrixHandlerTestHarness({
+        isDirectMessage: false,
+        roomsConfig: {
+          "!room:example.org": { requireMention: false },
+        },
+        shouldHandleTextCommands: () => true,
+        hasControlCommand,
+        cfg: {
+          commands: {
+            useAccessGroups: true,
+          },
+          channels: {
+            matrix: {
+              dm: { allowFrom: ["@observer:example.org"] },
+              groupAllowFrom: ["@driver:example.org"],
+            },
+          },
+        },
+        groupPolicy: "open",
+        getMemberDisplayName: async () => "observer",
+      });
+
+    await handler(
+      "!room:example.org",
+      createMatrixTextMessageEvent({
+        eventId: "$dm-configured-room-command",
+        sender: "@observer:example.org",
+        body: "@bot:example.org /new",
+      }),
+    );
+
+    expect(hasControlCommand).toHaveBeenCalledWith("/new", expect.anything());
+    expect(recordInboundSession).not.toHaveBeenCalled();
+    expect(finalizeInboundContext).not.toHaveBeenCalled();
+  });
+
   it("strips the Matrix self user id before room slash command detection", async () => {
     const hasControlCommand = vi.fn((text?: string) => text === "/new");
     const { handler, finalizeInboundContext, recordInboundSession } =