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CVE-2026-33425 (GCVE-0-2026-33425)

Vulnerability from cvelistv5 – Published: 2026-03-20 23:12 – Updated: 2026-03-23 16:48
VLAI
Title
Discourse has inferable private group membership or existence via exclude_groups parameter
Summary
Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, unauthenticated users can determine whether a specific user is a member of a private group by observing changes in directory results when using the `exclude_groups` parameter. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch. As a workaround, disable public access to the user directory via Admin → Settings → hide user profiles from public.
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-23 16:48 UTC
CWE
  • CWE-203 - Observable Discrepancy
  • CWE-639 - Authorization Bypass Through User-Controlled Key
  • CWE-862 - Missing Authorization
References
Impacted products
Vendor Product Version CPE status
discourse discourse Affected: >= 2026.1.0-latest, < 2026.1.2
Affected: >= 2026.2.0-latest, < 2026.2.1
Affected: = 2026.3.0-latest
guessed Create a notification for this product.
Show details on NVD website

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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

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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.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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