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CVE-2026-31805 (GCVE-0-2026-31805)

Vulnerability from cvelistv5 – Published: 2026-03-20 03:07 – Updated: 2026-03-20 15:46
VLAI
Title
Discourse has a poll authorization bypass via post_id array parameter
Summary
Discourse is an open-source discussion platform. Prior to versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2, an authorization bypass in the poll plugin allowed authenticated users to vote on, remove votes from, or toggle the open/closed status of polls they did not have access to. By passing post_id as an array (e.g. post_id[]=&post_id[]=), the authorization check resolves to the accessible post while the poll lookup resolves to a different post's poll. This affects the vote, remove_vote, and toggle_status endpoints in DiscoursePoll::PollsController. Versions 2026.3.0-latest.1, 2026.2.1, and 2026.1.2 contain a patch.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-20 15:46 UTC
CWE
  • CWE-863 - Incorrect Authorization
  • CWE-20 - Improper Input Validation
Assigner
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.1
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.

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  • 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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