PT-2025-49301 · Nextcloud · Nextcloud Talk

Published 2025-12-05 · Updated 2025-12-09 · CVE-2025-66556

Positive Technologies (AI Summary)

CVSS v3.1

4.3

Medium

Base vector

AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

Name of the Vulnerable Software and Affected Versions Nextcloud talk versions prior to 20.1.8 Nextcloud talk versions prior to 21.1.2

Description A participant with chat permissions could delete poll drafts of other participants within a conversation by using their numeric ID. This issue affects Nextcloud talk, a video and audio conferencing application for Nextcloud.

Recommendations Update Nextcloud talk to version 20.1.8 or later. Update Nextcloud talk to version 21.1.2 or later.

Exploit

Fix

IDOR

Weakness Enumeration

CWE-639

Related Identifiers

CVE-2025-66556

GHSA-PR9F-VQGG-M2JH

Affected Products

Nextcloud Talk

References · 12

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/66xxx/CVE-2025-66556.json · Exploit
• https://github.com/nextcloud/spreed/commit/bd68e80d1dea98d84c1d621c2c681238cf041725 · Patch
• https://github.com/nextcloud/spreed/pull/15532 · Patch
• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-pr9f-vqgg-m2jh · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2025-66556 · Security Note
• https://hackerone.com/reports/3247386 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2025-66556 · Vendor Advisory
• https://twitter.com/VulmonFeeds/status/1997120078991466584 · Twitter Post
• https://t.me/CVEtracker/38952 · Telegram Post
• https://twitter.com/dailycve/status/1998484264208281617 · Twitter Post
• https://t.me/cveNotify/145227 · Telegram Post
• https://twitter.com/CVEnew/status/1997009581000864197 · Twitter Post