Nextcloud talk allows participants to blindly delete poll drafts of other users by ID
CVE-2025-66556

3.5LOW

Key Information:

Vendor

Nextcloud
Status
Security-advisories
Vendor
CVE Published:
5 December 2025

What is CVE-2025-66556?

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.

Affected Version(s)

security-advisories < 20.1.8 < 20.1.8

security-advisories >= 21.0.0-beta.1, < 21.1.2 < 21.0.0-beta.1, 21.1.2

References

https://github.com/nextcloud/security-advisories/security...
x_refsource_CONFIRM
https://github.com/nextcloud/spreed/pull/15532
x_refsource_MISC
https://github.com/nextcloud/spreed/commit/bd68e80d1dea98...
x_refsource_MISC

CVSS V3.1

Score:
3.5
Severity:
LOW
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
Required
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

JSON
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CVE-2025-66556 : Nextcloud Talk Video & Audio Conferencing App Vulnerability in Poll Management