Opencast is free and open source software for automated video capture and distribution. First noticed in Opencast 13 and 14, Opencast's Elasticsearch integration may generate syntactically invalid Elasticsearch queries in relation to previously acceptable search queries. From Opencast version 11.4 and newer, Elasticsearch queries are retried a configurable number of times in the case of error to handle temporary losses of connection to Elasticsearch. These invalid queries would fail, causing the retry mechanism to begin requerying with the same syntactically invalid query immediately, in an infinite loop. This causes a massive increase in log size which can in some cases cause a denial of service due to disk exhaustion.
Opencast 13.10 and Opencast 14.3 contain patches which address the base issue, with Opencast 16.7 containing changes which harmonize the search behaviour between the admin UI and external API. Users are strongly recommended to upgrade as soon as possible if running versions prior to 13.10 or 14.3. While the relevant endpoints require (by default) ROLE_ADMIN or ROLE_API_SERIES_VIEW, the problem queries are otherwise innocuous. This issue could be easily triggered by normal administrative work on an affected Opencast system. Those who run a version newer than 13.10 and 14.3 and see different results when searching in their admin UI vs your external API or LMS, may resolve the issue by upgrading to 16.7. No known workarounds for the vulnerability are available.
| Software | From | Fixed in |
|---|---|---|
| apereo / opencast | 11.4 | 13.10 |
| apereo / opencast | 14.0 | 14.3 |
| apereo / opencast | 15.0 | 16.7 |
A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.
CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.
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Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.
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