Roundcube Webmail up to 1.6.19/1.7.4 FuncIRI to/from/by cross site scripting

Summaryinfo

A vulnerability classified as problematic was found in Roundcube Webmail up to 1.6.19/1.7.4. This issue affects some unknown processing of the component FuncIRI Handler. Executing a manipulation of the argument to/from/by can lead to cross site scripting. This vulnerability is registered as CVE-2026-114728. It is possible to launch the attack remotely. No exploit is available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in Roundcube Webmail up to 1.6.19/1.7.4 and classified as problematic. This vulnerability affects an unknown function of the component FuncIRI Handler. The manipulation of the argument to/from/by with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. CVE summarizes:

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.

The advisory is available at bugs.debian.org. This vulnerability was named CVE-2026-114728 since 10/22/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. Technical details are known, but there is no available exploit. This vulnerability is assigned to T1059.007 by the MITRE ATT&CK project.

Upgrading to version 1.6.20 or 1.7.5 eliminates this vulnerability.

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Productinfo

Type

• Mail Client Software

Vendor

• Roundcube

Name

• Webmail

Version

• 1.6.0
• 1.6.1
• 1.6.2
• 1.6.3
• 1.6.4
• 1.6.5
• 1.6.6
• 1.6.7
• 1.6.8
• 1.6.9
• 1.6.10
• 1.6.11
• 1.6.12
• 1.6.13
• 1.6.14
• 1.6.15
• 1.6.16
• 1.6.17
• 1.6.18
• 1.6.19
• 1.7.0
• 1.7.1
• 1.7.2
• 1.7.3
• 1.7.4

License

• free

CPE 2.3info

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CPE 2.2info

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