CVE-2026-33355 (GCVE-0-2026-33355)
Vulnerability from cvelistv5 – Published: 2026-03-19 22:01 – Updated: 2026-03-20 18:10
VLAI
EPSS
VEX
Title
Discourse filters whisper posts from private-posts feed
Summary
Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, the `/private-posts` endpoint did not apply post-type visibility filtering, allowing regular PM participants to see whisper posts in PM topics they had access to. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. No known workarounds are available.
Severity
6.5 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-20 17:00 UTC
CWE
- CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/discourse/discourse/security/a… | x_refsource_CONFIRM |
| https://github.com/discourse/discourse/commit/84e… | x_refsource_MISC |
| https://github.com/discourse/discourse/commit/d25… | x_refsource_MISC |
| https://github.com/discourse/discourse/commit/d2f… | x_refsource_MISC |
Impacted products
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{
"name": "https://github.com/discourse/discourse/commit/84e5865a279716c6866e8c0648d1d8b42320603c",
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"url": "https://github.com/discourse/discourse/commit/84e5865a279716c6866e8c0648d1d8b42320603c"
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"state": "PUBLISHED"
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}
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"lastModified": "2026-06-17T10:37:22.160",
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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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