CVE Tools
Sign in

CVE-2025-66554

Nextcloud Contacts vulnerable to Stored XSS in contacts app via organisation and title field

Published: Dec 5, 2025Updated: Dec 9, 2025 Sources: CVE List NVD BDUCWE-79
NVD MITRE
3.5CVSSLOW
EPSS Score
0.2%
Top 89.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available

Description

Contacts app for Nextcloud easily syncs contacts from various devices with your Nextcloud and allows editing. Prior to 5.5.4, 6.0.6, and 7.2.5, a malicious user was able to modify their organisation and title field to load additional CSS files. Javascript and other options were correctly blocked by the content security policy of the Nextcloud Server code. This vulnerability is fixed in 5.5.4, 6.0.6, and 7.2.5.

CVSS Vector Breakdown

AV:NAC:LPR:LUI:RS:UC:NI:LA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:LPrivileges Required
Low
UI:RUser Interaction
Required
Scope
S:UScope
Unchanged
Impact
C:NConfidentiality
None
I:LIntegrity
Low
A:NAvailability
None
Open in CVSS calculator →

Weaknesses

CWE-79

Affected Products

РЕД ОСООО «Ред Софт»
On-premOS
Operating Systems / linux-distro
ContactsNextcloud GmbH
SaaS
Cloud & SaaS / saas-application
contactsnextcloud
On-prem
Cloud & SaaS / saas-application
security-advisoriesnextcloud
SaaSSaaS Service
Cloud & SaaS / saas-application
ооо «ред софт»commercialRUOperating Systemsaka red soft
nextcloud gmbhcommercialDECloud & SaaSaka nextcloud server, nextcloud enterprise server, nextcloud calendar
nextcloudoss-projectDECloud & SaaSaka nextcloud server

Attack Graph

Products CVE Techniques Tactics

Click technique nodes to view MITRE ATT&CK details. Scroll to zoom, drag to pan.

Exploitability

Official Patch Available

MITRE ATT&CK

2 techniques
Execution
Initial Access
View detailed technique mapping

References

https://github.com/nextcloud/security-advisories/security/advisories/GHSA-9v78-cpfc-v6h2
github.com
http://repo.red-soft.ru/redos/8.0/x86_64/updates/
repo.red-soft.ru
https://github.com/nextcloud/contacts/commit/d954d098978dde1f121600e8b994e02f293c68b1
github.com
and 3 more references View all →

Timeline

Published
Dec 5, 2025
Last Updated
Dec 9, 2025

Unlock Complete Vulnerability Intelligence

Get the full picture for CVE-2025-66554 and every CVE in our database. Create a free account — no credit card required.

Create Free Account
Plain-language analysis
Impact assessment and exploitation scenario in plain English
Attack graph visualization
Interactive attack path and kill chain mapping
Exploit details & PoC links
ExploitDB, Metasploit, GitHub PoCs with direct links
Nuclei scanner templates
Ready-to-use vulnerability scanner templates
Full remediation guide
Patch instructions, workarounds, and compliance impact
Interactive AI chat
Ask questions about this vulnerability in natural language
Related vulnerabilities
Semantically similar CVEs and attack patterns
REST API & MCP access
Integrate vulnerability data into your workflows