CVE-2026-48843

Severity: high (CVSS 7.2 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-25 · updated 2026-07-24
Weakness: CWE-918

Description

Roundcube Webmail 1.6.x between 1.6.14 and 1.6.16,and 1.7.x before 1.7.1 has Insufficient Cascading Style Sheets (CSS) sanitization in HTML e-mail messages may lead to SSRF or Information Disclosure, e.g., if stylesheet links point to local network hosts. The issue stems from an insufficient fix for CVE-2026-35540.

Affected products

Roundcube Webmail: from 1.6.14 before 1.6.16; from 1.7.0 before 1.7.1 — fixed in 1.6.16, 1.7.1

How to fix

Upgrade to a fixed version: Roundcube Webmail 1.6.16, 1.7.1. Check the vendor advisory for mitigations.

References

https://github.com/roundcube/roundcubemail/commit/ab96c88bfd888866ec5e02190b19618db283923a
https://github.com/roundcube/roundcubemail/commit/cb3fc9041e91640ba9ba49ee7b2147c176ebf5a1
https://github.com/roundcube/roundcubemail/releases/tag/1.6.16
https://github.com/roundcube/roundcubemail/releases/tag/1.7.1
https://roundcube.net/news/2026/05/24/security-updates-1.6.16-and-1.7.1

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