CVE-2025-24808
MEDIUMCVSS Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Lifecycle Timeline
3Description
Discourse is an open-source discussion platform. Prior to versions `3.3.4` on the `stable` branch and `3.4.0.beta5` on the `beta` branch, someone who is about to reach the limit of users in a group DM may send requests to add new users in parallel. The requests might all go through ignoring the limit due to a race condition. The patch in versions `3.3.4` and `3.4.0.beta5` uses the `lock` step in service to wrap part of the `add_users_to_channel` service inside a distributed lock/mutex in order to avoid the race condition.
Analysis
Discourse is an open-source discussion platform. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, low attack complexity.
Technical Context
This vulnerability is classified under CWE-362. Discourse is an open-source discussion platform. Prior to versions `3.3.4` on the `stable` branch and `3.4.0.beta5` on the `beta` branch, someone who is about to reach the limit of users in a group DM may send requests to add new users in parallel. The requests might all go through ignoring the limit due to a race condition. The patch in versions `3.3.4` and `3.4.0.beta5` uses the `lock` step in service to wrap part of the `add_users_to_channel` service inside a distributed lock/mutex in order to avoid the race condition. Affected products include: Discourse.
Affected Products
Discourse.
Remediation
A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
Priority Score
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External POC / Exploit Code
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