CVE-2025-66514

CWE-79 — Cross-site Scripting (XSS)2 documents2 sources
Severity
5.4MEDIUM
EPSS
0.0%
top 92.42%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
2
Nextcloud MailNextcloud Security-advisories
Timeline
PublishedDec 5

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 vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:NExploitability: 2.1 | Impact: 1.4

Affected Packages2 packages

▶NVDnextcloud/mail< 5.5.3
▶CVEListV5nextcloud/security-advisories>= 5.2.0-beta.1, < 5.5.3

Patches

Patch: github.com ↗Patch: github.com ↗Patch: github.com ↗

🔴Vulnerability Details

1
CVEList
Nextcloud Mail stored HTML injection in subject text↗2025-12-05
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