GitHub Advisoryadvisory · Maven

GHSA-59g4-hpg3-3gcp Files Accessible to External Parties in Opencast

CRITICAL Published 2021-12-14 Modified 2022-01-04 Official page ↗
Aliases
CVE-2021-43821
Ecosystem
Maven
Packages
org.opencastproject:opencast-ingest-service-impl
Severity
Critical
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Weaknesses
CWE-552
Reviewed
2021-12-14

Affected packages

• Maven org.opencastproject:opencast-ingest-service-impl: < 10.6 → fixed in 10.6

Description

Opencast before version 10.6 allows references to local file URLs in ingested media packages, allowing attackers to include local files from Opencast's host machines and making them available via the web interface. Impact Before Opencast 10.6, Opencast would open and include local files during ingests. Attackers could exploit this to include most local files the process has read access to, extracting secrets from the host machine. For example, to expose the `custom.properties` of develop.opencast.org via the asset manager, an attacker could have run: ``` curl -f -i -u admin:opencast \ https://develop.opencast.org/ingest/addMediaPackage/fast \ -F 'flavor=presenter/source'\ -F mediaUri=file:///srv/opencast/opencast-dist-allinone/etc/custom.properties\ -F title="custom.properties" ``` An attacker would need to have the privileges required to add new media to exploit this. But these are often widely given. Patches The issue has been fixed in Opencast 10.6 and 11.0. Workarounds You can mitigate this issue by narrowing down the read access Opencast has to files on the file system using UNIX permissions or mandatory access control systems like SELinux. This cannot prevent access to files Opencast needs to read though and we highly recommend updating. References • Example of problematic code. • Patch fixing the issue For more information If you have any questions or comments about this advisory: • Open an issue in our issue tracker • Email us at [email protected]

Related

Alias · CVE (1)

  • CVE-2021-43821 Opencast is an Open Source Lecture Capture & Video Management for Education. vulnerability

Weakness · CWE (1)

  • CWE-552 Files or Directories Accessible to External Parties weakness

References