CVE-2026-114728

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-10-22 · updated 2026-10-29
Weakness: CWE-184

Description

Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by a remote content blocking bypass in the handling of FuncIRI attributes. rcube_washtml detected the CSS url() token with a pattern that enumerated only some of its escaped spellings, so values using other CSS escape sequences, for example \000075rl( or u\72 l(, were not recognized and remote content was loaded from an HTML message without the user's consent. Upstream fixed this in the commit “Fix remote content blocking bypass via CSS escapes in FuncIRI attributes (again)”, which resolves CSS escapes before matching and also inspects the `to`, `from` and `by` attributes.

Affected products

Roundcube Webmail: from 1.6.0 before 1.6.20; from 1.7.0 before 1.7.5 — fixed in 1.6.20, 1.7.5
Roundcube Webmail: from 1.6.0 before 1.6.20; from 1.7.0 before 1.7.5 — fixed in 1.6.20, 1.7.5

How to fix

Upgrade to a fixed version: Roundcube Webmail 1.6.20, 1.7.5; Roundcube Webmail 1.6.20, 1.7.5. Check the vendor advisory for mitigations.

References

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