5.5

CVE-2021-21318: apereo opencast Incorrect Authorization

CVSS: 5.5v2.0MediumModified
Published 18-02-2021Last modified 03-08-2024

Vulnerability summary

CVE-2021-21318 is a medium (CVSS 5.5) Incorrect Authorization vulnerability in apereo opencast. EPSS estimates a 0.71% chance of exploitation in the next 30 days, higher than 52.6% of scored vulnerabilities.

Overall risk
22/100
0100
Low · default modelHow is this calculated?
CVSS score
5.5/10
010
Medium · v2.0 (NVD)
EPSS score
0.71%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 18-02-2021
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

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.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

0.71%

Chance of exploitation in the next 30 days

Percentile

53%

Versus all other CVEs

30-day change

0.00 pp

From 0.71% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.71%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Apereo1 product
Opencast1 product

2 vendors · 2 products

References

2 links