{"cve":"CVE-2021-32623","nvd":{"published":"2021-06-16T00:15:07.717","modified":"2026-06-17T03:53:17.573","status":"Modified","description":"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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":6.5},"cwes":["CWE-776"],"references":["https://github.com/opencast/opencast/commit/8ae27da5a6f658011a5741b3210e715b0dc6213e","https://github.com/opencast/opencast/security/advisories/GHSA-9gwx-9cwp-5c2m","https://github.com/opencast/opencast/commit/8ae27da5a6f658011a5741b3210e715b0dc6213e","https://github.com/opencast/opencast/security/advisories/GHSA-9gwx-9cwp-5c2m"],"products":["apereo:opencast"],"source":"nvd","synced_at":"2026-10-19T21:20:07.141963181+00:00"},"epss":{"cve":"CVE-2021-32623","score":0.01254,"percentile":0.69484,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-9gwx-9cwp-5c2m","url":"https://osv.dev/vulnerability/GHSA-9gwx-9cwp-5c2m","summary":"Billion laughs attack (XML bomb)","modified":"2026-07-08T06:29:26.344912944Z","packages":[{"ecosystem":"Maven","name":"org.opencastproject:opencast-kernel","purl":"pkg:maven/org.opencastproject/opencast-kernel","ranges":["<9.6"],"fixed":["9.6"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}