#VU59086 Files or Directories Accessible to External Parties in Opencast - CVE-2021-43821

Vulnerability identifier: #VU59086

Vulnerability risk: Medium

CVSSv4.0: 5.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2021-43821

CWE-ID: CWE-552

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
Opencast
Other software / Other software solutions

Vendor: Apereo Foundation

Description

The vulnerability allows a remote user to gain access to sensitive information.

The vulnerability exists due to a logic error that allows references to local file URLs in ingested media packages. A remote user can include arbitrary local files from Opencast's host machine and make them publicly available via the web interface.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Opencast: 1.3.0 - 10.5, 2.0.0 - 2.3.5, 3.0 - 3.7, 4.0 - 4.5, 5.0 - 5.5, 6.0 - 6.7, 7.0 - 7.9, 8.0 - 8.11, 9.0 - 9.10

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External links
https://github.com/opencast/opencast/security/advisories/GHSA-59g4-hpg3-3gcp
https://github.com/opencast/opencast/blob/69952463971cf578363e3b97d8edaf334ff51253/modules/ingest-service-impl/src/main/java/org/opencastproject/ingest/impl/IngestServiceImpl.java#L1587
https://mvnrepository.com/artifact/org.opencastproject/opencast-ingest-service-impl
https://github.com/opencast/opencast/commit/65c46b9d3e8f045c544881059923134571897764

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.