CVE-2026-55087mediumCWE-444CWE-601CWE-79

CVE-2026-55087: fallo de gravedad media en etherpad

Etherpad: x-proxy-path header reflected into admin HTML/JS/CSS (cache-poisoning XSS) and concatenated into redirect (open-redirect)

Publicada el · Actualizada el

Seguir esta CVE+ Monitorear etherpad+ Monitorear ep_etherpad-lite

Aviso por correo cuando entre en el KEV, tenga PoC pública o suba de nota.

28Vexday Risk Score

Corrige pronto. Ella tiene exploit funcional público.

ssvc Attendcvss 6.1epss 0.6%
Etherpad is a real-time collaborative editor. From 2.1.0 until 3.1.0, Etherpad uses the attacker-controlled x-proxy-path request header in src/node/hooks/express/admin.ts when substituting paths into HTML, JavaScript, and CSS under /admin without sanitization, Vary: x-proxy-path, or Cache-Control: private, no-store. A shared proxy or CDN can cache the resulting response and serve attacker-injected script to an administrator. In src/node/hooks/express/specialpages.ts, version 3.0.0 also accepts a protocol-relative x-proxy-path value when constructing the /p/:pad/timeslider redirect, allowing redirection to an attacker-controlled host. The issues are exploitable when the deployment permits client-supplied x-proxy-path headers to reach Etherpad. This issue is fixed in version 3.1.0.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Productos afectados
ether · etherpad
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