CVE-2026-77614

high

Description

Opencast is a free, open-source platform to support the management of educational audio and video content. Prior to versions 19.7 and 20.2, the default security configuration in etc/security/mh_default_org.xml accepts a client-selected JSESSIONID from the ;jsessionid= URL path parameter and does not replace it when the victim logs in. An unauthenticated attacker can send a crafted link to a victim whose browser has no active Opencast session cookie, wait for the victim to authenticate, and then reuse the known identifier as the victim's authenticated session. This can expose the victim's data and actions and can produce full administrative account takeover when the victim is an administrator. This issue is fixed in versions 19.7 and 20.2.

References

https://github.com/opencast/opencast/security/advisories/GHSA-6f53-jp7x-gg7p

https://github.com/opencast/opencast/releases/tag/20.2

https://github.com/opencast/opencast/releases/tag/19.7

https://github.com/opencast/opencast/commit/ff84128c9b3bcbd79c28192d25929dab8faf185f

https://github.com/opencast/opencast/commit/c36652250a026afb7cf78b663950c702669f1d3f

Details

Source: Mitre, NVD

Published: 2026-09-17

Updated: 2026-09-17

Risk Information

CVSS v2

Base Score: 10

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

Severity: Critical

CVSS v3

Base Score: 8.8

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Severity: High

EPSS

EPSS: 0.00405