From 52c7a51cfc568ed61d800df99dcca25dc3b5fe3e Mon Sep 17 00:00:00 2001 From: reivilibre <38398653+reivilibre@users.noreply.github.com> Date: Tue, 31 Aug 2021 10:09:58 +0100 Subject: [PATCH 1/4] Merge pull request from GHSA-3x4c-pq33-4w3q * Add some tests to characterise the problem Some failing. Current states: RoomsMemberListTestCase test_get_member_list ... [OK] test_get_member_list_mixed_memberships ... [OK] test_get_member_list_no_permission ... [OK] test_get_member_list_no_permission_former_member ... [OK] test_get_member_list_no_permission_former_member_with_at_token ... [FAIL] test_get_member_list_no_room ... [OK] test_get_member_list_no_permission_with_at_token ... [FAIL] * Correct the tests * Check user is/was member before divulging room membership * Pull out only the 1 membership event we want. * Update tests/rest/client/v1/test_rooms.py Co-authored-by: Erik Johnston * Fixup tests (following apply review suggestion) Co-authored-by: Erik Johnston --- synapse/handlers/message.py | 23 ++++++-- tests/rest/client/v1/test_rooms.py | 84 +++++++++++++++++++++++++++++- 2 files changed, 103 insertions(+), 4 deletions(-) diff --git a/synapse/handlers/message.py b/synapse/handlers/message.py index 8a0024ce84..101a29c6d3 100644 --- a/synapse/handlers/message.py +++ b/synapse/handlers/message.py @@ -183,20 +183,37 @@ class MessageHandler: if not last_events: raise NotFoundError("Can't find event for token %s" % (at_token,)) + last_event = last_events[0] + + # check whether the user is in the room at that time to determine + # whether they should be treated as peeking. + state_map = await self.state_store.get_state_for_event( + last_event.event_id, + StateFilter.from_types([(EventTypes.Member, user_id)]), + ) + + joined = False + membership_event = state_map.get((EventTypes.Member, user_id)) + if membership_event: + joined = membership_event.membership == Membership.JOIN + + is_peeking = not joined visible_events = await filter_events_for_client( self.storage, user_id, last_events, filter_send_to_client=False, + is_peeking=is_peeking, ) - event = last_events[0] if visible_events: room_state_events = await self.state_store.get_state_for_events( - [event.event_id], state_filter=state_filter + [last_event.event_id], state_filter=state_filter ) - room_state: Mapping[Any, EventBase] = room_state_events[event.event_id] + room_state: Mapping[Any, EventBase] = room_state_events[ + last_event.event_id + ] else: raise AuthError( 403, diff --git a/tests/rest/client/v1/test_rooms.py b/tests/rest/client/v1/test_rooms.py index 0c9cbb9aff..50100a5ae4 100644 --- a/tests/rest/client/v1/test_rooms.py +++ b/tests/rest/client/v1/test_rooms.py @@ -29,7 +29,7 @@ from synapse.api.constants import EventContentFields, EventTypes, Membership from synapse.api.errors import HttpResponseException from synapse.handlers.pagination import PurgeStatus from synapse.rest import admin -from synapse.rest.client import account, directory, login, profile, room +from synapse.rest.client import account, directory, login, profile, room, sync from synapse.types import JsonDict, RoomAlias, UserID, create_requester from synapse.util.stringutils import random_string @@ -381,6 +381,8 @@ class RoomPermissionsTestCase(RoomBase): class RoomsMemberListTestCase(RoomBase): """Tests /rooms/$room_id/members/list REST events.""" + servlets = RoomBase.servlets + [sync.register_servlets] + user_id = "@sid1:red" def test_get_member_list(self): @@ -397,6 +399,86 @@ class RoomsMemberListTestCase(RoomBase): channel = self.make_request("GET", "/rooms/%s/members" % room_id) self.assertEquals(403, channel.code, msg=channel.result["body"]) + def test_get_member_list_no_permission_with_at_token(self): + """ + Tests that a stranger to the room cannot get the member list + (in the case that they use an at token). + """ + room_id = self.helper.create_room_as("@someone.else:red") + + # first sync to get an at token + channel = self.make_request("GET", "/sync") + self.assertEquals(200, channel.code) + sync_token = channel.json_body["next_batch"] + + # check that permission is denied for @sid1:red to get the + # memberships of @someone.else:red's room. + channel = self.make_request( + "GET", + f"/rooms/{room_id}/members?at={sync_token}", + ) + self.assertEquals(403, channel.code, msg=channel.result["body"]) + + def test_get_member_list_no_permission_former_member(self): + """ + Tests that a former member of the room can not get the member list. + """ + # create a room, invite the user and the user joins + room_id = self.helper.create_room_as("@alice:red") + self.helper.invite(room_id, "@alice:red", self.user_id) + self.helper.join(room_id, self.user_id) + + # check that the user can see the member list to start with + channel = self.make_request("GET", "/rooms/%s/members" % room_id) + self.assertEquals(200, channel.code, msg=channel.result["body"]) + + # ban the user + self.helper.change_membership(room_id, "@alice:red", self.user_id, "ban") + + # check the user can no longer see the member list + channel = self.make_request("GET", "/rooms/%s/members" % room_id) + self.assertEquals(403, channel.code, msg=channel.result["body"]) + + def test_get_member_list_no_permission_former_member_with_at_token(self): + """ + Tests that a former member of the room can not get the member list + (in the case that they use an at token). + """ + # create a room, invite the user and the user joins + room_id = self.helper.create_room_as("@alice:red") + self.helper.invite(room_id, "@alice:red", self.user_id) + self.helper.join(room_id, self.user_id) + + # sync to get an at token + channel = self.make_request("GET", "/sync") + self.assertEquals(200, channel.code) + sync_token = channel.json_body["next_batch"] + + # check that the user can see the member list to start with + channel = self.make_request( + "GET", "/rooms/%s/members?at=%s" % (room_id, sync_token) + ) + self.assertEquals(200, channel.code, msg=channel.result["body"]) + + # ban the user (Note: the user is actually allowed to see this event and + # state so that they know they're banned!) + self.helper.change_membership(room_id, "@alice:red", self.user_id, "ban") + + # invite a third user and let them join + self.helper.invite(room_id, "@alice:red", "@bob:red") + self.helper.join(room_id, "@bob:red") + + # now, with the original user, sync again to get a new at token + channel = self.make_request("GET", "/sync") + self.assertEquals(200, channel.code) + sync_token = channel.json_body["next_batch"] + + # check the user can no longer see the updated member list + channel = self.make_request( + "GET", "/rooms/%s/members?at=%s" % (room_id, sync_token) + ) + self.assertEquals(403, channel.code, msg=channel.result["body"]) + def test_get_member_list_mixed_memberships(self): room_creator = "@some_other_guy:red" room_id = self.helper.create_room_as(room_creator) From cb35df940a828bc40b96daed997b5ad4c7842fd3 Mon Sep 17 00:00:00 2001 From: reivilibre <38398653+reivilibre@users.noreply.github.com> Date: Tue, 31 Aug 2021 11:24:09 +0100 Subject: [PATCH 2/4] Merge pull request from GHSA-jj53-8fmw-f2w2 --- synapse/groups/groups_server.py | 18 ++++++++-- tests/rest/client/v2_alpha/test_groups.py | 43 +++++++++++++++++++++++ 2 files changed, 59 insertions(+), 2 deletions(-) create mode 100644 tests/rest/client/v2_alpha/test_groups.py diff --git a/synapse/groups/groups_server.py b/synapse/groups/groups_server.py index 3dc55ab861..d6b75ac27f 100644 --- a/synapse/groups/groups_server.py +++ b/synapse/groups/groups_server.py @@ -332,6 +332,13 @@ class GroupsServerWorkerHandler: requester_user_id, group_id ) + # Note! room_results["is_public"] is about whether the room is considered + # public from the group's point of view. (i.e. whether non-group members + # should be able to see the room is in the group). + # This is not the same as whether the room itself is public (in the sense + # of being visible in the room directory). + # As such, room_results["is_public"] itself is not sufficient to determine + # whether any given user is permitted to see the room's metadata. room_results = await self.store.get_rooms_in_group( group_id, include_private=is_user_in_group ) @@ -341,8 +348,15 @@ class GroupsServerWorkerHandler: room_id = room_result["room_id"] joined_users = await self.store.get_users_in_room(room_id) + + # check the user is actually allowed to see the room before showing it to them + allow_private = requester_user_id in joined_users + entry = await self.room_list_handler.generate_room_entry( - room_id, len(joined_users), with_alias=False, allow_private=True + room_id, + len(joined_users), + with_alias=False, + allow_private=allow_private, ) if not entry: @@ -354,7 +368,7 @@ class GroupsServerWorkerHandler: chunk.sort(key=lambda e: -e["num_joined_members"]) - return {"chunk": chunk, "total_room_count_estimate": len(room_results)} + return {"chunk": chunk, "total_room_count_estimate": len(chunk)} class GroupsServerHandler(GroupsServerWorkerHandler): diff --git a/tests/rest/client/v2_alpha/test_groups.py b/tests/rest/client/v2_alpha/test_groups.py new file mode 100644 index 0000000000..bfa9336baa --- /dev/null +++ b/tests/rest/client/v2_alpha/test_groups.py @@ -0,0 +1,43 @@ +from synapse.rest.client.v1 import room +from synapse.rest.client.v2_alpha import groups + +from tests import unittest +from tests.unittest import override_config + + +class GroupsTestCase(unittest.HomeserverTestCase): + user_id = "@alice:test" + room_creator_user_id = "@bob:test" + + servlets = [room.register_servlets, groups.register_servlets] + + @override_config({"enable_group_creation": True}) + def test_rooms_limited_by_visibility(self): + group_id = "+spqr:test" + + # Alice creates a group + channel = self.make_request("POST", "/create_group", {"localpart": "spqr"}) + self.assertEquals(channel.code, 200, msg=channel.text_body) + self.assertEquals(channel.json_body, {"group_id": group_id}) + + # Bob creates a private room + room_id = self.helper.create_room_as(self.room_creator_user_id, is_public=False) + self.helper.auth_user_id = self.room_creator_user_id + self.helper.send_state( + room_id, "m.room.name", {"name": "bob's secret room"}, tok=None + ) + self.helper.auth_user_id = self.user_id + + # Alice adds the room to her group. + channel = self.make_request( + "PUT", f"/groups/{group_id}/admin/rooms/{room_id}", {} + ) + self.assertEquals(channel.code, 200, msg=channel.text_body) + self.assertEquals(channel.json_body, {}) + + # Alice now tries to retrieve the room list of the space. + channel = self.make_request("GET", f"/groups/{group_id}/rooms") + self.assertEquals(channel.code, 200, msg=channel.text_body) + self.assertEquals( + channel.json_body, {"chunk": [], "total_room_count_estimate": 0} + ) From 8c26f16c76b475e0ace7b58920d90368b180454c Mon Sep 17 00:00:00 2001 From: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> Date: Tue, 31 Aug 2021 12:56:22 +0100 Subject: [PATCH 3/4] Fix up unit tests (#10723) These were broken in an incorrect merge of GHSA-jj53-8fmw-f2w2 (cb35df9) --- changelog.d/10723.bugfix | 1 + tests/rest/client/v2_alpha/test_groups.py | 17 +++++++++++++++-- 2 files changed, 16 insertions(+), 2 deletions(-) create mode 100644 changelog.d/10723.bugfix diff --git a/changelog.d/10723.bugfix b/changelog.d/10723.bugfix new file mode 100644 index 0000000000..e6ffdc9512 --- /dev/null +++ b/changelog.d/10723.bugfix @@ -0,0 +1 @@ +Fix unauthorised exposure of room metadata to communities. diff --git a/tests/rest/client/v2_alpha/test_groups.py b/tests/rest/client/v2_alpha/test_groups.py index bfa9336baa..ad0425ae65 100644 --- a/tests/rest/client/v2_alpha/test_groups.py +++ b/tests/rest/client/v2_alpha/test_groups.py @@ -1,5 +1,18 @@ -from synapse.rest.client.v1 import room -from synapse.rest.client.v2_alpha import groups +# Copyright 2021 The Matrix.org Foundation C.I.C. +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. + +from synapse.rest.client import groups, room from tests import unittest from tests.unittest import override_config From a4c8a2f08b735266fbbe2f259e640f00dc5e3a00 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Tue, 31 Aug 2021 13:42:51 +0100 Subject: [PATCH 4/4] 1.41.1 --- CHANGES.md | 32 ++++++++++++++++++++++++++++++++ debian/changelog | 6 ++++++ synapse/__init__.py | 2 +- 3 files changed, 39 insertions(+), 1 deletion(-) diff --git a/CHANGES.md b/CHANGES.md index f8da8771aa..fab27b874e 100644 --- a/CHANGES.md +++ b/CHANGES.md @@ -1,3 +1,35 @@ +Synapse 1.41.1 (2021-08-31) +=========================== + +Due to the two security issues highlighted below, server administrators are encouraged to update Synapse. We are not aware of these vulnerabilities being exploited in the wild. + +Security advisory +----------------- + +The following issues are fixed in v1.41.1. + +- **[GHSA-3x4c-pq33-4w3q](https://github.com/matrix-org/synapse/security/advisories/GHSA-3x4c-pq33-4w3q) / [CVE-2021-39164](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-39164): Enumerating a private room's list of members and their display names.** + + If an unauthorized user both knows the Room ID of a private room *and* that room's history visibility is set to `shared`, then they may be able to enumerate the room's members, including their display names. + + The unauthorized user must be on the same homeserver as a user who is a member of the target room. + + Fixed by [52c7a51cf](https://github.com/matrix-org/synapse/commit/52c7a51cf). + +- **[GHSA-jj53-8fmw-f2w2](https://github.com/matrix-org/synapse/security/advisories/GHSA-jj53-8fmw-f2w2) / [CVE-2021-39163](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-39163): Disclosing a private room's name, avatar, topic, and number of members.** + + If an unauthorized user knows the Room ID of a private room, then its name, avatar, topic, and number of members may be disclosed through Group / Community features. + + The unauthorized user must be on the same homeserver as a user who is a member of the target room, and their homeserver must allow non-administrators to create groups (`enable_group_creation` in the Synapse configuration; off by default). + + Fixed by [cb35df940a](https://github.com/matrix-org/synapse/commit/cb35df940a), [\#10723](https://github.com/matrix-org/synapse/issues/10723). + +Bugfixes +-------- + +- Fix a regression introduced in Synapse 1.41 which broke email transmission on systems using older versions of the Twisted library. ([\#10713](https://github.com/matrix-org/synapse/issues/10713)) + + Synapse 1.41.0 (2021-08-24) =========================== diff --git a/debian/changelog b/debian/changelog index 4da4bc018c..5f7a795b6e 100644 --- a/debian/changelog +++ b/debian/changelog @@ -1,3 +1,9 @@ +matrix-synapse-py3 (1.41.1) stable; urgency=high + + * New synapse release 1.41.1. + + -- Synapse Packaging team Tue, 31 Aug 2021 12:59:10 +0100 + matrix-synapse-py3 (1.41.0) stable; urgency=medium * New synapse release 1.41.0. diff --git a/synapse/__init__.py b/synapse/__init__.py index ef3770262e..06d80f79b3 100644 --- a/synapse/__init__.py +++ b/synapse/__init__.py @@ -47,7 +47,7 @@ try: except ImportError: pass -__version__ = "1.41.0" +__version__ = "1.41.1" if bool(os.environ.get("SYNAPSE_TEST_PATCH_LOG_CONTEXTS", False)): # We import here so that we don't have to install a bunch of deps when