calibre is an e-book manager. Prior to 9.12.0, the calibre Content Server endpoint POST /book-update-annotations/{libraryid}/{bookid}/{fmt} in src/calibre/srv/books.py omits needsdbwrite=True, causing Router.dispatch() to skip ctx.checkforwriteaccess() before updateannotations() passes attacker-controlled JSON to db.mergeannotationsfor_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_ids": [
"CWE-862"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/73xxx/CVE-2026-73249.json",
"cna_assigner": "GitHub_M"
}