CVE-2026-77166 json
The emoji field in the page emoji update endpoint does not properly validate user input.
published 2026-09-21 48 d ago modified 2026-09-22 47 d ago also EUVD-2026-83972
- cvss
- 2.4
- version 3.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 21%
- public exploits
- 0
- none known
Summary
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.
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 48 d ago
Exploit prediction
0.28% chance of exploitation in the next 30 days, higher than 21% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- hackerone.com https://hackerone.com/reports/3599470 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.0 | 2.4 | CVSS:3.0/AV:N/AC:L/PR:H/UI:R/S:U/C:N/I:L/A:N |
Affected products
- Nextcloud Collectives
Classification
- Weakness
-
- CWE-840 Business Logic Errors
References
-
hackerone.com
/reports/3599470
exploit
Sources
- CVE List CVE-2026-77166
- NVD CVE-2026-77166
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.