CVE-2025-66556 (GCVE-0-2025-66556)

Vulnerability from cvelistv5 – Published: 2025-12-05 17:56 – Updated: 2025-12-05 18:09
VLAI
Title
Nextcloud talk allows participants to blindly delete poll drafts of other users by ID
Summary
Nextcloud talk is a video & audio conferencing app for Nextcloud. Prior to 20.1.8 and 21.1.2, a participant with chat permissions was able to delete poll drafts of other participants within the conversation based on their numeric ID. This vulnerability is fixed in 20.1.8 and 21.1.2.
Severity
3.5 (Low)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
CWE
  • CWE-639 - Authorization Bypass Through User-Controlled Key
Assigner
References
Impacted products
Vendor Product Version
nextcloud security-advisories Affected: < 20.1.8
Affected: >= 21.0.0-beta.1, < 21.1.2
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Taxonomy of the tags.




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.



Detection rules are retrieved from Rulezet.