CVE-2026-114722

MEDIUM
MEDIUM Priority: 0.02 BB Relevance: 73/100
Published: 2026-10-22 Modified: 2026-10-28 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: Unchanged
C: Low
I: Low
A: None

Description

Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by a CSS scoping bypass in HTML messages. rcube_utils::mod_css_styles() did not treat an at-rule prologue such as @layer a; as a selector boundary, and did not handle selectors beginning with ::, so selectors following an at-rule were left unscoped and applied to the whole Roundcube interface instead of being confined to the message body. This allows an HTML message to restyle application chrome for UI redressing and spoofing. Upstream fixed this in the commit “Fix CSS scoping bypass in HTML messages using at-rules”.

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
Roundcube Webmail 1.6.0 < 1.6.20

Bug Bounty Relevance

73 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

6.5 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

EPSS — Exploitation Probability

0.25%
Raw Score 0.002520
Percentile 16.7%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00252
2026-10-28
0.00252

Intelligence Sources

mitre ref →
nvd ref →