{"id":"CVE-2026-85295","published":"2026-11-06T21:17:10.890","lastModified":"2026-11-09T23:17:26.347","description":"Chartbrew is an open-source web application that can connect directly to databases and APIs and use the data to create charts. Prior to 5.2.3, four authentication helpers accepted session tokens signed with CB_SECRET, including known, weak, or shipped-default values. The vulnerable surface is session JWT fallback in server/modules/verifyToken.js, verifyUser.js, getUserFromToken.js, and socketManager.js across the API and socket layer. A stock source or repository Docker Compose deployment retains a known, weak, or default CB_SECRET and an attacker submits a forged HS256 token decoding to a target user id. Knowing the symmetric secret lets the attacker create a token that the legacy verification fallback accepts as the target user without that user's password or two-factor authentication. The condition includes stock source and repository Docker Compose installs and any otherwise known or weak CB_SECRET; a bare container where CB_SECRET is undefined is not affected by this fallback path. A forged session impersonates the chosen user across the entire API and socket layer and exercises that user's Chartbrew privileges. This issue is fixed in version 5.2.3.","cvssScore":9.8,"cvssSeverity":"CRITICAL","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwes":["CWE-1394"],"vendors":[],"products":[],"references":[{"url":"https://github.com/chartbrew/chartbrew/commit/da8c71f156aaa13fbc7ead15a4726740fef2b3c5","tags":[]},{"url":"https://github.com/chartbrew/chartbrew/releases/tag/v5.2.3","tags":[]},{"url":"https://github.com/chartbrew/chartbrew/security/advisories/GHSA-qvv4-r3q6-8797","tags":[]}],"exploitRefs":[{"url":"https://github.com/chartbrew/chartbrew/commit/da8c71f156aaa13fbc7ead15a4726740fef2b3c5","tags":[]},{"url":"https://github.com/chartbrew/chartbrew/releases/tag/v5.2.3","tags":[]},{"url":"https://github.com/chartbrew/chartbrew/security/advisories/GHSA-qvv4-r3q6-8797","tags":[]}],"hasPoc":true,"ai":{"summary":"Chartbrew versions prior to 5.2.3 are vulnerable to authentication bypass via forged JWT session tokens signed with weak or default CB_SECRET values, allowing attackers to impersonate any user—including admin—without credentials or MFA.","exploitability":"Exploitation is trivial for attackers who can obtain or guess a known/weak/default CB_SECRET (e.g., from stock Docker Compose deployments), requiring only JWT forgery and submission of the forged token.","blast_radius":"Successful exploitation grants full API and socket-layer access as the impersonated user, enabling data exfiltration, configuration tampering, and full system compromise if the target has elevated privileges.","remediation":"Upgrade to Chartbrew version 5.2.3 or later; for deployments where upgrading is not immediately possible, rotate CB_SECRET to a cryptographically strong random value and ensure it is never reused or exposed in configuration files or logs.","detection":"Monitor for repeated JWT verification failures with HS256 algorithm and mismatched issuer/subject claims in API and socket logs, especially when tokens decode to unexpected user IDs; also watch for anomalous bulk API requests from a single session that lacks prior authentication history.","tags":["auth-bypass","jwt-forgery","default-credentials","session-hijack","web-app"],"model":"garnet-coder","analyzedAt":"2026-11-07T09:55:00.421Z"}}