CVE-2026-73249
calibre Content Server `/book-update-annotations` Missing Write Authorization Check Allows Unauthorized Annotation Modification
CVSS Score
7.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-862 |
| Vendor | kovidgoyal |
| Product | calibre |
| Published | Aug 11, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None
Affected Versions
kovidgoyal / calibre
< 9.12.0