CVE-2026-35540

EUVD-2026-18583
An issue was discovered in Roundcube Webmail 1.6.0 before 1.6.14. 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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
5.4 MEDIUM
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N
mitreCNA
5.4 MEDIUM
NETWORK
HIGH
NONE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Affected Products (NVD)
VendorProductVersion
roundcubewebmail
1.6.0 ≤
𝑥
< 1.6.14
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
roundcube
bookworm
vulnerable
bookworm (security)
vulnerable
bullseye
vulnerable
bullseye (security)
1.4.15+dfsg.1-1+deb11u8
fixed
forky
1.6.15+dfsg-1
fixed
sid
1.6.15+dfsg-1
fixed
trixie
vulnerable
trixie (security)
vulnerable
Common Weakness Enumeration
References
https://github.com/roundcube/roundcubemail/commit/27ec6cc9cb25e1ef8b4d4ef39ce76d619caa6870
https://github.com/roundcube/roundcubemail/commit/579b68eff90650a5c782e153debd66c765648942
https://github.com/roundcube/roundcubemail/releases/tag/1.6.14
https://github.com/roundcube/roundcubemail/releases/tag/1.7-rc5
https://roundcube.net/news/2026/03/18/security-updates-1.7-rc5-1.6.14-1.5.14