Auth bypass in Readest

CVE-2026-57562

Readest is a modern, feature-rich ebook reader designed for seamless cross-platform access and an intuitive reading experience. Prior to 0.11.10, POST /api/stripe/check in apps/readest-app/src/app/api/stripe/check/route.ts accepted a client-controlled sessionId, retrieved the corresponding Stripe Checkout Session, and granted the paid plan to the authenticated caller without verifying session.metadata.userId. The createOrUpdateSubscription path then updated the plans row keyed by the caller's user identifier rather than the Checkout Session owner. Any authenticated free user with a paid active Checkout Session identifier, including one from the user's own single legitimate purchase, could replay that identifier to upgrade additional accounts without payment. This issue is fixed in version 0.11.10.

Vulnerability class: IDOR (Insecure Direct Object Reference)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-57562?
CVE-2026-57562 is a medium-severity vulnerability in Readest, classified under Authorization Bypass Through User-Controlled Key. CVSS score: 6.5/10. Published 2026-11-04.
How severe is CVE-2026-57562?
Medium severity. CVSS v3 base score is 6.5 out of 10.