CyberSecBulletin
CVE-2024-52797NVD status: Modified

opencast: Allocation of Resources Without Limits or Throttling

CVE-2024-52797 is a high-severity allocation of resources without limits or throttling vulnerability in opencast, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected opencast versions: >= 11.4, < 13.10; >= 14.0, < 14.3; >= 15.0, < 16.7. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.92% chance of exploitation within 30 days, higher than 61% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of opencast you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Opencastopencast>= 11.4, < 13.10; >= 14.0, < 14.3; >= 15.0, < 16.7Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.16.5MediumCNA (github.com)
CVSS 3.17.5HighNVD

Official description

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.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Allocation of Resources Without Limits or Throttling

The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.

How developers prevent this class of flaw

  • Clearly specify the minimum and maximum expectations for capabilities, and dictate which behaviors are acceptable when resource allocation reaches limits.
  • Limit the amount of resources that are accessible to unprivileged users. Set per-user limits for resources. Allow the system administrator to define these limits. Be careful to avoid CWE-410.
  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

More Allocation of Resources Without Limits or Throttling vulnerabilities (CWE-770)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in opencast

All opencast vulnerabilities

Recent Allocation of Resources Without Limits or Throttling vulnerabilities

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