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CVE-2021-32623

Opencast vulnerable to billion laughs attack (XML bomb)

Published: Jun 15, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSACWE-776

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 Vector Breakdown

AV:NAC:LPR:LUI:NS:UC:NI:HA:H
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:HIntegrity
High
A:HAvailability
High

Weaknesses

Affected Products

mavenpackage-ecosystemOSS Libraries
apereooss-projectCloud & SaaSaka opencast, central authentication service, cas, phpcas

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

1 exploit source identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

MITRE ATT&CK

1 technique
Impact
View detailed technique mapping

References

and 2 more references View all →

Timeline

Published
Jun 15, 2021
Last Updated
Nov 21, 2024

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