{"id":"CVE-2026-55241","title":"Checkmate is an open-source, self-hosted tool designed to track and monitor server hardware, uptime, response times, and incidents in real-time with beautiful visualizations","summary":"Checkmate is an open-source, self-hosted tool designed to track and monitor server hardware, uptime, response times, and incidents in real-time with beautiful visualizations. Prior to 3.9.1, the public POST /api/v1/auth/register route in…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-400","CWE-770"],"published":"2026-08-21","updated":"2026-09-18","sourceUpdated":"2026-09-18T20:09:01.757","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-55241","references":[{"url":"https://github.com/bluewave-labs/Checkmate/commit/091c36cbf338b673110b0806d76df26d52516468","label":"security-advisories@github.com"},{"url":"https://github.com/bluewave-labs/Checkmate/releases/tag/v3.9.1","label":"security-advisories@github.com"},{"url":"https://github.com/bluewave-labs/Checkmate/security/advisories/GHSA-9xvg-x28f-m78m","label":"security-advisories@github.com"},{"url":"https://github.com/bluewave-labs/Checkmate/security/advisories/GHSA-9xvg-x28f-m78m","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"tags":["nvd"],"epss":0.00555,"epssPercentile":0.45156,"ingestedAt":"2026-09-18T20:51:25.655Z","slug":"CVE-2026-55241","body":"## Overview\n\nCheckmate is an open-source, self-hosted tool designed to track and monitor server hardware, uptime, response times, and incidents in real-time with beautiful visualizations. Prior to 3.9.1, the public POST /api/v1/auth/register route in server/src/api/routes/authRoutes.ts passes multipart profileImage uploads through in-memory Multer parsing before registration validation, without file-size, file-count, or MIME-type limits in server/src/api/middleware/upload.ts. An unauthenticated attacker can submit concurrent oversized files that are buffered before invalid registration or invite-token checks reject the request, exhausting memory and crashing or destabilizing the backend. This issue is fixed in version 3.9.1.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":41,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}