CVE-2026-55690 is a high-severity cross-site scripting (XSS) vulnerability in starcitizenwiki/embedvideo (composer), affecting versions <= 4.0.0. It is fixed in 4.1.0.
Summary When passing an unknown service name to embedvideo, an error message is rendered containing the invalid service name. The service name is not sanitized and can contain HTML. Details There is a hardcoded list of allowed services in a switch statement inside EmbedServiceFactory#newFromName here. When the service name is not known, an exception is thrown with the service name injected into the message via sprintf here. This message is not sanitized and is marked as isHtml here. Similarly with {{evl: here. PoC Impact Stored XSS that allows arbitrary Javascript/HTML insertion on any page that a user can edit. It requires no interaction and executes in the wiki origin for every visitor to the page.
Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.
CVE-2026-55690 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment.
A fixed version is available (4.1.0). Upgrading removes the vulnerable code path.
composer
starcitizenwiki/embedvideo (<= 4.0.0)starcitizenwiki/embedvideo → 4.1.0 (composer)Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter instead of chasing every advisory.
Kodem's runtime-powered SCA identifies whether CVE-2026-55690 is reachable in your applications. Explore open-source security for your team.
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Upgrade starcitizenwiki/embedvideo to 4.1.0 or later to resolve this vulnerability.
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
CVE-2026-55690 is a high-severity cross-site scripting (XSS) vulnerability in starcitizenwiki/embedvideo (composer), affecting versions <= 4.0.0. It is fixed in 4.1.0. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
CVE-2026-55690 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
starcitizenwiki/embedvideo (composer) versions <= 4.0.0 is affected.
Yes. CVE-2026-55690 is fixed in 4.1.0. Upgrade to this version or later.
Whether CVE-2026-55690 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
Upgrade starcitizenwiki/embedvideo to 4.1.0 or later.