CVE-2025-48053: Discourse vulnerable to DoS via large URL payload in PM to a bot

Published Jun 9, 2025
·
Updated

Discourse is an open-source discussion platform. Prior to version 3.4.4 of the stable branch, version 3.5.0.beta5 of the beta branch, and version 3.5.0.beta6-dev of the tests-passed branch, sending a malicious URL in a PM to a bot user can cause a reduced the availability of a Discourse instance. This issue is patched in version 3.4.4 of the stable branch, version 3.5.0.beta5 of the beta branch, and version 3.5.0.beta6-dev of the tests-passed branch. No known workarounds are available.

Affected Software

6 affected components
Discourse Discourse<3.4.4
Discourse Discourse<3.5.0
Discourse Discourse=3.5.0-beta1
Discourse Discourse=3.5.0-beta2
Discourse Discourse=3.5.0-beta3
Discourse Discourse=3.5.0-beta4

Event History

Jun 9, 2025
CVE Published
via MITRE·12:30 PM
Data Sourced
via MITRE·12:30 PM
DescriptionWeakness
Data Sourced
via NVD·01:15 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2025-48053?

CVE-2025-48053 has a high severity due to the potential for reduced availability when handling malicious URLs.

2

How do I fix CVE-2025-48053?

To fix CVE-2025-48053, update to Discourse version 3.4.4 or newer on the stable branch, or version 3.5.0.beta5 or newer on the beta branch.

3

What versions are affected by CVE-2025-48053?

CVE-2025-48053 affects Discourse versions earlier than 3.4.4 on the stable branch and versions prior to 3.5.0.beta5 on the beta branch.

4

What type of vulnerability is CVE-2025-48053?

CVE-2025-48053 is a security vulnerability that can lead to denial of service through manipulation of private messages.

5

Who is impacted by CVE-2025-48053?

Users of Discourse prior to the specified versions are at risk from CVE-2025-48053, especially if interacting with bot users.

Contact

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