Vulnerability · Published Dec 5, 2025 · Assigned by GitHub_M
CVE-2025-66556Nextcloud talk allows participants to blindly delete poll drafts of other users by ID
Low 3.5
In plain English
A low-severity authorization bypass via user-controlled key in security-advisories from nextcloud. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 20% of all known vulnerabilities).
Severity (CVSS 3.1)3.5Low
Exploit odds (30 days)0.3%top 80.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
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 products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| nextcloud | security-advisories | < 20.1.8>= 21.0.0-beta.1, < 21.1.2 |
Weakness: CWE-639 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
References
- https://github.com/nextcloud/security-advisories/security/advisories/GHSA-pr9f-vqgg-m2jh x_refsource_CONFIRM
- https://github.com/nextcloud/spreed/pull/15532 x_refsource_MISC
- https://github.com/nextcloud/spreed/commit/bd68e80d1dea98d84c1d621c2c681238cf041725 x_refsource_MISC
- https://hackerone.com/reports/3247386 x_refsource_MISC