Vulnerability · Published Sep 21, 2026 · Assigned by hackerone
CVE-2026-77166
Low 2.4
In plain English
A low-severity security flaw in Collectives from Nextcloud. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 21% of all known vulnerabilities).
Severity (CVSS 3.0)2.4Low
Exploit odds (30 days)0.3%top 78.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
The emoji field in the page emoji update endpoint does not properly validate user input. By injecting long text and line breaks, the sidebar layout becomes broken and can hide other items.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Nextcloud | Collectives | 3.2.1 – through 3.5.0 |
Weakness: CWE-840 · Vector: CVSS:3.0/AV:N/AC:L/PR:H/UI:R/S:U/C:N/I:L/A:N