Description
Nextcloud Mail is the mail app for Nextcloud, a self-hosted productivity platform. Prior to 5.5.3, a stored HTML injection in the Mail app's message list allowed an authenticated user to inject HTML into the email subjects. Javascript was correctly blocked by the content security policy of the Nextcloud Server code.
CVSS Metrics
- Vector
- CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
- Attack Vector
- network
- Complexity
- low
- Privileges
- low
- User Action
- required
- Scope
- unchanged
- Confidentiality
- none
- Integrity
- low
- Availability
- none
- Weaknesses
- CWE-79
Metadata
- Primary Vendor
- NEXTCLOUD
- Published
- 12/5/2025
- Last Modified
- 12/9/2025
- Source
- NIST NVD
- Note: Verify all details with official vendor sources before applying patches.
Affected Products
nextcloud : mail
AI-Powered Remediation
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