CVE-2023-25819: Discourse tags with no visibility are leaking into og:article:tag

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-03-04 · updated 2026-06-17
Weakness: CWE-359

Description

Discourse is an open source platform for community discussion. Tags that are normally private are showing in metadata. This affects any site running the `tests-passed` or `beta` branches >= 3.1.0.beta2. The issue is patched in the latest `beta` and `tests-passed` version of Discourse.

Affected products

discourse: before 3.1.0; 3.1.0-beta1, 3.1.0-beta2 — fixed in 3.1.0

How to fix

Upgrade to a fixed version: discourse 3.1.0. Check the vendor advisory for mitigations.

References

https://github.com/discourse/discourse/commit/a9f2c6db64e7d78b8e0f55e7bd77c5fe3459b831
https://github.com/discourse/discourse/security/advisories/GHSA-xx2h-mwm7-hq6q
https://github.com/discourse/discourse/commit/a9f2c6db64e7d78b8e0f55e7bd77c5fe3459b831
https://github.com/discourse/discourse/security/advisories/GHSA-xx2h-mwm7-hq6q

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