CVE-2026-57565
Received Received - Intake

Path Traversal in Readest Ebook Reader

Vulnerability report for CVE-2026-57565, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.

Publication date: 2026-11-04

Last updated on: 2026-11-04

Assigner: GitHub, Inc.

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.

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Meta Information

Published
2026-11-04
Last Modified
2026-11-04
Generated
2026-11-05
AI Q&A
2026-11-05
EPSS Evaluated
N/A
NVD

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
readest readest < 0.11.10

Helpful Resources

Exploitability

CWE
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KEV
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CWE ID Description
CWE-22 The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

Attack-Flow Graph

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Executive Summary

Readest is an ebook reader app. Before version 0.11.10, it had a flaw in how it handled file uploads. The app allowed authenticated users to upload files using a path that could include directory traversal sequences like ../. When combined with URL normalization in the R2 backend, this let attackers escape their designated storage space and overwrite files belonging to other users.

Impact Analysis

If you used Readest before version 0.11.10, an attacker who knew your user ID and a book hash could overwrite your stored books or corrupt metadata. This could lead to data loss, incorrect book content, or disruption of your reading experience.

Compliance Impact

This vulnerability could violate data integrity and access control requirements in GDPR and HIPAA. Unauthorized file overwrites may constitute a data breach, exposing personal or health information to tampering. Compliance could be impacted due to unauthorized access and potential data corruption.

Mitigation Strategies

Update Readest to version 0.11.10 or later to address the path traversal issue in the storage upload route.

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