CVE-2026-27153 PUBLISHED

Discourse doesn't prevent moderators from exporting user Chat DMs

Assigner: GitHub_M
Reserved: 18.02.2026 Published: 26.02.2026 Updated: 26.02.2026

Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, moderators could export user Chat DMs via the CSV export endpoint by exploiting an overly permissive allowlist in can_export_entity?. The method allowed moderators to export any entity not explicitly blocked instead of restricting to an explicit allowlist. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. No known workarounds are available.

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U
CVSS Score: 1.3

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	None	Confidentiality	None
Attack Complexity	Low	Integrity	Low	Integrity	None
Attack Requirements	None	Availability	None	Availability	None
Privileges Required	Low
User Interaction	None

CVSS 4.0

Product Status

Vendor	discourse
Product	discourse
Versions	Version < 2025.12.2 is affected Version >= 2026.1.0-latest, < 2026.1.1 is affected Version >= 2026.2.0-latest, < 2026.2.0 is affected

References

https://github.com/discourse/discourse/security/advisories/GHSA-5cp2-jq8m-33mf

Problem Types

CWE-863: Incorrect Authorization CWE