CVE-2026-77166 Details
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.
A denial-of-service vulnerability has been identified in the Nextcloud Collectives app version 4.0.0. The issue arises from the emoji field in the page emoji update endpoint, which fails to properly validate user input. This lack of validation allows users to inject excessively long strings, including newline characters, instead of valid emojis. As a result, the sidebar layout is disrupted, causing the injected content to overlap and hide other items. This interference prevents users from accessing different pages within the collective.
This vulnerability has been addressed in the latest maintenance releases of Nextcloud.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Sep 21, 2026CISA-ADP
Assessed Sep 21, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://hackerone.com/reports/3599470 | CISA-ADP | ExploitIssue TrackingTechnical DescriptionVendor |
| https://hackerone.com/reports/3599470 | [email protected] | ExploitIssue TrackingTechnical DescriptionVendor |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-840 | Business Logic Errors | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| Nextcloud Collectives | 4.0.0 (semver) |
CPE
Remediation
| |
Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Sep 21, 2026 | CVE Modified | CISA-ADP |
| Sep 21, 2026 | New CVE Received | [email protected] |