CVE-2024-21658Network attack vector

Service degradation via oversized holiday-region values

Published Aug 30, 2024 · Updated Aug 30, 2024

Uncontrolled resource consumption in Discourse Calendar allows remote authenticated users to exhaust server disk space and bandwidth. The editable holidays-region user field accepts an excessively long string that calendar processing stores and transmits without a sufficiently restrictive limit. A low-privileged account can submit the field over the network, increasing storage and response traffic until service availability is degraded.

CVSS severity4.3
Medium
EPSS probability0.36%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uncontrolled resource consumption in Discourse Calendar allows remote authenticated users to exhaust server disk space and bandwidth. The editable holidays-region user field accepts an excessively long string that calendar processing stores and transmits without a sufficiently restrictive limit. A low-privileged account can submit the field over the network, increasing storage and response traffic until service availability is degraded.

The record

CVE
CVE-2024-21658
Published
Aug 30, 2024
Updated
Aug 30, 2024
Vendor
Discourse
Product
Discourse Calendar
Classifications
CWE-400, CWE-770, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 30, 2024CVE publishedPublication date reported by the CVE source.
  2. Aug 30, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 66259cd21dc6a1b2139d9833f3f847d8013e6759

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Discourse · Discourse Calendarversion=< 66259cd21dc6a1b2139d9833f3f847d8013e6759

Published CVSS scores

4.3GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
4.3NIST National Vulnerability DatabaseCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
CWE-770Allocation of Resources Without Limits or Throttling
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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