CVE-2026-73249
HighCVSS 7.5Exploitation Probability (EPSS)
Low risk23th percentile - higher than 23% of all known CVEs
Summary
calibre is an e-book manager. Prior to 9.12.0, the calibre Content Server endpoint POST /book-update-annotations/{library_id}/{book_id}/{fmt} in src/calibre/srv/books.py omits needs_db_write=True, causing Router.dispatch() to skip ctx.check_for_write_access() before update_annotations() passes attacker-controlled JSON to db.merge_annotations_for_book(), which allows a readonly user or an anonymous user on an unauthenticated deployment to persist unauthorized book annotation changes. This issue is fixed in version 9.12.0.
Risk Assessment
Unauthorized users can modify book annotations, potentially leading to data integrity and trust issues.
Recommendation
Update calibre to version 9.12.0 or later. Ensure Content Server access is properly secured.
Other vulnerabilities in calibre
See all- CVE-2026-73248High
Calibre before version 9.12.0 processes attacker-controlled composite_template metadata from malicious EPUB, OPF, PDF, or similar files through program: and a nested template() call whose formatter does not inherit allow_python_templates=False, allowing a nested python: template to reach compile_python_template and execute arbitrary Python code when the file is opened or imported. This issue is fixed in version 9.12.0.
- CVE-2026-53511High
A vulnerability in calibre prior to version 9.10.0 allows arbitrary Python code execution via a malicious EPUB, OPF, or PDF file. An attacker can embed a custom column definition with a python: template in calibre:user_metadata that is passed unsanitized to exec() in the template formatter.
Original NVD description (English source)
calibre is an e-book manager. Prior to 9.12.0, the calibre Content Server endpoint POST /book-update-annotations/{library_id}/{book_id}/{fmt} in src/calibre/srv/books.py omits needs_db_write=True, causing Router.dispatch() to skip ctx.check_for_write_access() before update_annotations() passes attacker-controlled JSON to db.merge_annotations_for_book(), which allows a readonly user or an anonymous user on an unauthenticated deployment to persist unauthorized book annotation changes. This issue is fixed in version 9.12.0.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS