Elastic search: Search results are not restricted for aretfacts on pages shared with group

[Lisa Seeto]

A user can create a page with media artefacts on it and share it with a group. The user can specify which users in that group have access, i.e "Everyone in group", "Member" and "Admin". When a user selects to share the page with "Member" or "Admin" all members of the group can view via the media category in Elastic Search page and can see the artefact. The preview image for an Image block for this issue is displaying as a broken link in FireFox and not displaying at all in Chrome.

Have Elastic Search set up and able to search.
1. Create a group that has admin and members.
2. Log in as a user (doesn't have to be group member) and create a page with an Image block.
3. Share the page with the group and choose "Admin" in dropdown
4. Log in as an Member of the group and go to Elastic search with no search words (should return everything you have access to see.
5. Select Media tab and view
Expected results:
No artefacts from pages that are not shared with User are returned as results.
Actual results:
User can see artefacts from the page they do not have permission to access.

Mahara: 19.10dev
OS: Ubunt 18.04.2
DB: Postgres
Browser: Firefox 68.01, Chrome 75.0.3770.142

[Kristina Hoeppner (kris-hoeppner)]

Marking as high as it's to do with permissions and thus privacy.

[Kristina Hoeppner (kris-hoeppner)]

Please check if also a problem in 19.04.

[Kristina Hoeppner (kris-hoeppner)]

This will need to be tested with isolated institutions turned on as well.

[Robert Lyon (robertl-9)]

https://reviews.mahara.org/#/c/10770/

[Kristina Hoeppner (kris-hoeppner)]

Information for the security forum post:

Vulnerability type: Incorrect access control
Attack type: Remote
Impact: Information disclosure
Affected: Elasticsearch implementation in Mahara

In Mahara 18.10 before 18.10.5, 19.04 before 19.04.4, and 19.10 before 19.10.2, file metadata information is disclosed to group members in the Elasticsearch result list despite them not having access to to that information any more.

Reference: https://bugs.launchpad.net/mahara/+bug/1840201
Credit: Lisa Seeto and Robert Lyon (Catalyst IT)

CVE: CVE-2020-9386
(link CVE number to: https://cve.mitre.org/cgi-bin/cvename.cgi?name=2020-9386 )

[Mahara Bot (dev-mahara)]

Patch for "19.04_STABLE" branch: https://reviews.mahara.org/10819

[Mahara Bot (dev-mahara)]

Reviewed: https://reviews.mahara.org/10819
Committed: https://git.mahara.org/mahara/mahara/commit/41c210f3b6a66e520d7ea6b460b3615d7b839f8d
Submitter: Robert Lyon (<email address hidden>)
Branch: 19.04_STABLE

commit 41c210f3b6a66e520d7ea6b460b3615d7b839f8d
Author: Robert Lyon <email address hidden>
Date: Wed Mar 11 09:46:28 2020 +1300

Bug 1866913: Add parts of missing function from master that are needed

Fix for bug 1840201 in 19.04

Change-Id: I20f41cb9557f3fa24a48e7e05a185ab1f72e5658
Signed-off-by: Robert Lyon <email address hidden>

[Mahara Bot (dev-mahara)]

Patch for "18.10_STABLE" branch: https://reviews.mahara.org/10838

[Mahara Bot (dev-mahara)]

Reviewed: https://reviews.mahara.org/10838
Committed: https://git.mahara.org/mahara/mahara/commit/42332f7c547376781e539c84340347921bfcc546
Submitter: Robert Lyon (<email address hidden>)
Branch: 18.10_STABLE

commit 42332f7c547376781e539c84340347921bfcc546
Author: Robert Lyon <email address hidden>
Date: Wed Mar 11 09:46:28 2020 +1300

Bug 1866913: Add parts of missing function from master that are needed

Fix for bug 1840201 in 19.04

Change-Id: I20f41cb9557f3fa24a48e7e05a185ab1f72e5658
Signed-off-by: Robert Lyon <email address hidden>
(cherry picked from commit 41c210f3b6a66e520d7ea6b460b3615d7b839f8d)