{"id":"CVE-2026-57565","published":"2026-11-04T22:18:06.680","lastModified":"2026-11-04T22:18:06.680","description":"Readest is a modern, feature-rich ebook reader designed for seamless cross-platform access and an intuitive reading experience. Prior to 0.11.10, the apps/readest-app/src/pages/api/storage/upload.ts route constructed an object key from the authenticated user's identifier and a client-controlled fileName without rejecting path separators or parent-directory traversal. In the R2 backend, apps/readest-app/src/utils/r2.ts placed that key into a new Request URL before signing it, and URL normalization collapsed parent-directory components so the resulting presigned PUT could escape the caller's namespace. An authenticated attacker who knew a target user identifier and book hash could overwrite or poison that user's stored book object and corrupt the associated file_key metadata; the exact cross-tenant escape was verified for the R2 backend. This issue is fixed in version 0.11.10.","cvssScore":6.5,"cvssSeverity":"MEDIUM","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N","cwes":["CWE-22"],"vendors":[],"products":[],"references":[{"url":"https://github.com/readest/readest/commit/495783d04516d05b2eb10f8f8bad297d436b36de","tags":[]},{"url":"https://github.com/readest/readest/pull/4638","tags":[]},{"url":"https://github.com/readest/readest/releases/tag/v0.11.10","tags":[]},{"url":"https://github.com/readest/readest/security/advisories/GHSA-mfmj-2frf-vhgw","tags":[]}],"exploitRefs":[{"url":"https://github.com/readest/readest/commit/495783d04516d05b2eb10f8f8bad297d436b36de","tags":[]},{"url":"https://github.com/readest/readest/pull/4638","tags":[]},{"url":"https://github.com/readest/readest/releases/tag/v0.11.10","tags":[]},{"url":"https://github.com/readest/readest/security/advisories/GHSA-mfmj-2frf-vhgw","tags":[]}],"hasPoc":true,"ai":null}