CVE-2025-66514

published 2025-12-05

CVE-2025-66514: 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…

Priority P4 26 medium 5.4 CVSS 3.1

AV N AC L PR L UI R S C C L I L A N

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.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
nextcloud	mail	< 5.5.3	5.5.3
nextcloud	security-advisories	—	—

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CWE-79