CVE-2025-66556

Nextcloud talk allows participants to blindly delete poll drafts of other users by ID

3.5 Low

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.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: Low
User interaction: Required

What an attacker can affect

Confidentiality: None
Integrity: Low
Availability: None

Exploit likelihood

0.27%Up 0.3 points since Dec 6, 2025

What each source reports

CVE List Score used 3.5

Nextcloud talk allows participants to blindly delete poll drafts of other users by ID

Record: CVE-2025-66556
CVSS 3.1: 3.5 LowCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
Weakness: CWE-639
Updated: 2026-11-02

EUVDEUVD-2025-201458 3.5

Record: EUVD-2025-201458
CVSS 3.1: 3.5 LowCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
Updated: 2026-11-02

NVD 3.5

Record: CVE-2025-66556
CVSS 3.1: 3.5 LowCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
CVSS 3.1: 4.3 MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Weakness: CWE-639
Updated: 2026-11-02

OSV 3.5

Nextcloud talk allows participants to blindly delete poll drafts of other users by ID

Record: CVE-2025-66556
CVSS 3.1: 3.5 LowCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
Weakness: CWE-639
Updated: 2026-11-02

Affected products

History

History
Recorded	Changed	Sources
Nov 2, 2026	first indexed	CVE List, EUVD, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2025-66556 is a low vulnerability (CVSS 3.5) in Nextcloud Talk, published December 5, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.27%, the 19th percentile. No source names a fixed version.