CVE-2022-46150: Discourse may allow exposure of hidden tags in the subject of notification emails

Severity: medium (CVSS 4.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2022-11-29 · updated 2026-06-17
Weakness: CWE-200

Description

Discourse is an open-source discussion platform. Prior to version 2.8.13 of the `stable` branch and version 2.9.0.beta14 of the `beta` and `tests-passed` branches, unauthorized users may learn of the existence of hidden tags and that they have been applied to topics that they have access to. This issue is patched in version 2.8.13 of the `stable` branch and version 2.9.0.beta14 of the `beta` and `tests-passed` branches. As a workaround, use the `disable_email` site setting to disable all emails to non-staff users.

Affected products

discourse: before 2.8.13; 2.9.0-beta1, 2.9.0-beta10, 2.9.0-beta11, 2.9.0-beta12, 2.9.0-beta13, 2.9.0-beta2 (+6) — fixed in 2.8.13

How to fix

Upgrade to a fixed version: discourse 2.8.13. Check the vendor advisory for mitigations.

References

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