CVE-2026-27935 (GCVE-0-2026-27935)
Vulnerability from cvelistv5 – Published: 2026-03-19 21:33 – Updated: 2026-03-20 16:28
VLAI
EPSS
VEX
Title
Discourse leaks private topic metadata to non-authorized users
Summary
Discourse is an open-source discussion platform. Versions prior to 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 have a vulnerability in an API endpoint that discloses private topic metadata of admin users to moderator users even if the moderators do not have access to the private topics. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. No known workarounds are available.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-20 16:28 UTC
CWE
- CWE-201 - Insertion of Sensitive Information Into Sent Data
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/discourse/discourse/security/a… | x_refsource_CONFIRM |
| https://github.com/discourse/discourse/commit/c0f… | x_refsource_MISC |
| https://github.com/discourse/discourse/commit/d8d… | x_refsource_MISC |
| https://github.com/discourse/discourse/commit/f37… | x_refsource_MISC |
Impacted products
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"modifiedSubConfidentialityImpact": "NOT_DEFINED",
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Nomenclature
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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.
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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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