CVE-2021-21318 Removing access may not effect published series
Attackers can retain unauthorized access to series metadata by exploiting flawed access control updates during episode removal or republishing.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2021-21318?
CVE-2021-21318 is a medium-severity missing authorization vulnerability in opencast, published on 18 Feb 2021. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Opencast is a free, open-source platform to support the management of educational audio and video content. In Opencast before version 9.2 there is a vulnerability in which publishing an episode with strict access rules will overwrite the currently set series access. This allows for an easy denial of access for all users without superuser privileges, effectively hiding the series. Access to series and series metadata on the search service (shown in media module and player) depends on the events published which are part of the series. Publishing an event will automatically publish a series and update access to it. Removing an event or republishing the event should do the same. Affected versions of Opencast may not update the series access or remove a published series if an event is being removed. On removal of an episode, this may lead to an access control list for series metadata with broader access rules than the merged access rules of all remaining events, or the series metadata still being available although all episodes of that series have been removed. This problem is fixed in Opencast 9.2.
Weakness: CWE-863
Which versions are affected by CVE-2021-21318?
It affects 1 product.
Products include Apereo Opencast.
How do I fix CVE-2021-21318?
No fix has been published for CVE-2021-21318 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2021-21318 being exploited?
There is no known exploitation of CVE-2021-21318 in the wild and no public exploit code.
Other vulnerabilities in opencast
- CVE-2021-43821 Files Accessible to External Parties in Opencast
- CVE-2020-5206 Authentication Bypass For Endpoints With Anonymous Access in OpenCast
- CVE-2021-32623 Opencast vulnerable to billion laughs attack (XML bomb)
- CVE-2020-5229 Opencast stores passwords using outdated MD5 hash algorithm
- CVE-2020-5230 Opencast uses unsafe identifiers
Sources
Also known as GHSA-vpc2-3wcv-qj4w.