[USN-8223-1] Roundcube Webmail vulnerabilities

========================================================================== Ubuntu Security Notice USN-8223-1 April 29, 2026 roundcube vulnerabilities ========================================================================== A security issue affects these releases of Ubuntu and its derivatives: - Ubuntu 24.04 LTS - Ubuntu 22.04 LTS - Ubuntu 20.04 LTS - Ubuntu 18.04 LTS - Ubuntu 16.04 LTS Summary: Several security issues were fixed in Roundcube Webmail. Software Description: - roundcube: skinnable AJAX based webmail solution for IMAP servers - metapackage Details: It was discovered that Roundcube Webmail mishandled Punycode xn-- domain names. An attacker could possibly use this issue to cause a homograph attack. (CVE-2019-15237) It was discovered that Roundcube Webmail did not properly sanitize certain attributes when handling CSS within HTML messages and certain SVG attributes. An attacker could possibly use this issue to cause a cross-site scripting attack. (CVE-2024-38356, CVE-2024-38357) It was discovered that Roundcube Webmail did not properly sanitize certain HTML attributes when rendering e-mail messages. An attacker could possibly use this issue to cause a cross-site scripting attack. (CVE-2024-42008) It was discovered that Roundcube Webmail did not properly filter certain CSS token sequences within rendered e-mail messages. An attacker could possibly use this issue to obtain sensitive information. (CVE-2024-42010) It was discovered that Roundcube Webmail did not properly treat an SVG tag as an image source within its HTML sanitizer. An attacker could possibly use this issue to bypass remote image blocking to track email open actions or potentially bypass access control. (CVE-2026-25916) It was discovered that Roundcube Webmail did not properly handle comments within Cascading Style Sheets (CSS). An attacker could possibly use this issue to perform a CSS injection attack. (CVE-2026-26079) Update instructions: The problem can be corrected by updating your system to the following package versions: Ubuntu 24.04 LTS roundcube-core 1.6.6+dfsg-2ubuntu0.1+esm3 Available with Ubuntu Pro Ubuntu 22.04 LTS roundcube-core 1.5.0+dfsg.1-2ubuntu0.1~esm6 Available with Ubuntu Pro roundcube-plugins 1.5.0+dfsg.1-2ubuntu0.1~esm6 Available with Ubuntu Pro Ubuntu 20.04 LTS roundcube-core 1.4.3+dfsg.1-1ubuntu0.1~esm8 Available with Ubuntu Pro roundcube-plugins 1.4.3+dfsg.1-1ubuntu0.1~esm8 Available with Ubuntu Pro Ubuntu 18.04 LTS roundcube-core 1.3.6+dfsg.1-1ubuntu0.1~esm8 Available with Ubuntu Pro roundcube-plugins 1.3.6+dfsg.1-1ubuntu0.1~esm8 Available with Ubuntu Pro Ubuntu 16.04 LTS roundcube-core 1.2~beta+dfsg.1-0ubuntu1+esm8 Available with Ubuntu Pro roundcube-plugins 1.2~beta+dfsg.1-0ubuntu1+esm8 Available with Ubuntu Pro In general, a standard system update will make all the necessary changes. References: https://ubuntu.com/security/notices/USN-8223-1 CVE-2019-15237, CVE-2024-38356, CVE-2024-38357, CVE-2024-42008, CVE-2024-42010, CVE-2026-25916, CVE-2026-26079