CVE-2025-48053 - CVE House
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Status published High CVE-2025-48053

Discourse vulnerable to DoS via large URL payload in PM to a bot

Vulnerability Description

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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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CVE-2025-68934
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CVE-2025-68933
Discourse non-admin moderators can exfiltrate private content via post ownership transfer
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Discourse users archives leaked to users with moderation privileges
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Affected Vendor

Affected Software

discourse
Vulnerable Versions:
< 3.4.4, < 3.5.0.beta5, < 3.5.0.beta6-dev

Timeline

Official Publish: June 9th, 2025
Last Modified: June 9th, 2025
Added to House: July 22nd, 2026

CVSS Vectors

Weaknesses (CWE)

CWE-400 CWE-770

MITRE ATT&CK TTPs

T1499 Endpoint Denial of Service
Impact
T1498 Network Denial of Service
Impact
T1190 Exploit Public-Facing Application
Initial Access
T1562 Impair Defenses
Defense Evasion
T1046 Network Service Discovery
Discovery