XXE in Apereo Opencast
CVE-2021-32623
Opencast is a free and open source solution for automated video capture and distribution. Versions of Opencast prior to 9.6 are vulnerable to the billion laughs attack, which allows an attacker to easily execute a (seemingly permanent) denial of service attack, essentially taking down Opencast using a single HTTP request. To exploit this, users need to have ingest privileges, limiting the group of potential attackers The problem has been fixed in Opencast 9.6. There is no known workaround for this issue.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H.
EPSS exploit prediction
EPSS: 0.013 (69.0th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 69th percentile — 69.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.013 · newest: 0.013 · change: 0.000
Affected products
- Apereo Opencast
- Opencast — versions < 9.6
Weakness classification (CWE)
References
- github.com/opencast/opencast/security/advisories/GHSA-9gwx-9cwp-5c2m (Exploit, Third Party Advisory)
- github.com/opencast/opencast/commit/8ae27da5a6f658011a5741b3210e715b0dc6213e (Patch, Third Party Advisory)
Frequently asked questions
- What is CVE-2021-32623?
- CVE-2021-32623 is a high-severity vulnerability in Apereo Opencast, classified under Improper Restriction of Recursive Entity References in DTDs (XML Entity Expansion). CVSS score: 8.1/10. Published 2021-06-16.
- How severe is CVE-2021-32623?
- High severity. CVSS v3 base score is 8.1 out of 10.