CVE-2026-28227 (GCVE-0-2026-28227)
Vulnerability from cvelistv5 – Published: 2026-02-26 21:27 – Updated: 2026-03-03 14:44
VLAI
EPSS
VEX
Title
Discourse Vulnerable to Unauthorized Topic Creation in Staff-Only Categories via Topic Timer publish_to_category
Summary
Discourse is an open source discussion platform. Prior to versions 2025.12.2, 2026.1.1, and 2026.2.0, TL4 users can publish topics into staff-only categories via the `publish_to_category` topic timer, bypassing authorization checks. Versions 2025.12.2, 2026.1.1, and 2026.2.0 patch the issue. No known workarounds are available.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-03 14:44 UTC
CWE
- CWE-863 - Incorrect Authorization
Assigner
References
1 reference
| URL | Tags |
|---|---|
| https://github.com/discourse/discourse/security/a… | x_refsource_CONFIRM |
Impacted products
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}
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"configurations": [
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},
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"value": "Discourse es una plataforma de discusi\u00f3n de c\u00f3digo abierto. Antes de las versiones 2025.12.2, 2026.1.1 y 2026.2.0, los usuarios TL4 pueden publicar temas en categor\u00edas solo para el personal a trav\u00e9s del temporizador de temas \u0027publish_to_category\u0027, omitiendo las comprobaciones de autorizaci\u00f3n. Las versiones 2025.12.2, 2026.1.1 y 2026.2.0 parchean el problema. No se conocen soluciones alternativas disponibles."
}
],
"id": "CVE-2026-28227",
"lastModified": "2026-06-17T10:28:22.143",
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"scope": "UNCHANGED",
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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