CVEvulnerability

CVE-2026-55087

6.1 MEDIUM Published 2026-08-19 Modified 2026-09-09 Official page ↗
Status
Deferred
Published
2026-08-19
Last modified
2026-09-09
Assigner
[email protected]
CVSS 3.1 ([email protected])
6.1 MEDIUM — CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Weaknesses
CWE-444, CWE-601, CWE-79

Description

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.

Related

Weakness · CWE (3)

  • CWE-444 Inconsistent Interpretation of HTTP Requests weakness
  • CWE-601 URL Redirection to Untrusted Site weakness
  • CWE-79 Improper Neutralization of Input During Web Page Generation weakness

References