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TI-2026-51386 Aliases CVE-2026-73249

Missing authorization in kovidgoyal calibre

Priority HIGH 72CWE-862Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-862.

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00436 38th percentileScored 2026-11-07
Fix Fixed calibre (kovidgoyal): 9.12.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
kovidgoyalcalibrebefore 9.12.09.12.0Patch availableCNA
  • calibre Vendorkovidgoyal Affected before 9.12.0 Fixed in 9.12.0 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:calibre-ebook:calibre:*:*:*:*:*:*:*:*——Calibre
  • cpe:2.3:a:calibre-ebook:calibre:*:*:*:*:*:*:*:* Versions — — ·Calibre

Remediation

  • Fix · CNA calibre (kovidgoyal) Fixed in 9.12.0

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-73249

References

Other 3

  • TI-2026-26023 Kitty has a Heap Buffer Over-Read/Write via Integer Overflow in compose_rectangles Bounds Check CVSS 3.1CRITICAL 9.9
  • TI-2026-51129 Kitty: Command injection into the child shell via chained @kitty-echo + @kitty-ssh DCS escape sequences CVSS 4.0HIGH 7.3
  • TI-2026-26014 Kitty has a Heap Buffer Overflow in its Graphics Protocol Handler CVSS 3.1HIGH 8.8
  • TI-2026-51385 calibre: Bypass of Python template restrictions via nested `template()` leading to RCE CVSS 4.0HIGH 8.5
  • TI-2026-38585 calibre: Arbitrary Code Execution in Template Formatter via Book Metadata CVSS 4.0HIGH 8.5
  • TI-2026-25627 calibre has a path traversal vulnerability CVSS 4.0HIGH 8.2
See all 29 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences