CVE-2026-73249Public exploitNetwork attack vectorHinoki check available

Unauthorized annotation modification via missing write authorization

Published Aug 11, 2026 · Updated Aug 11, 2026

Missing authorization in Kovid Goyal calibre before 9.12.0 allows remote attackers to modify stored book annotations through the Content Server. The POST /book-update-annotations route omits needs_db_write=True, so Router.dispatch skips the write check before attacker-controlled JSON reaches merge_annotations_for_book. Reachability requires access to a target book; readonly credentials suffice with authentication enabled, while anonymous access suffices when it is disabled.

CVSS severity7.5
High
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Missing authorization in Kovid Goyal calibre before 9.12.0 allows remote attackers to modify stored book annotations through the Content Server. The POST /book-update-annotations route omits needs_db_write=True, so Router.dispatch skips the write check before attacker-controlled JSON reaches merge_annotations_for_book. Reachability requires access to a target book; readonly credentials suffice with authentication enabled, while anonymous access suffices when it is disabled.

The record

CVE
CVE-2026-73249
Published
Aug 11, 2026
Updated
Aug 11, 2026
Vendor
Kovid Goyal
Product
calibre
Classifications
CWE-862, T1565.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 11, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 11, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 9.12.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Kovid Goyal · calibreversion=< 9.12.0

Published CVSS scores

7.5GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-862Missing Authorization
T1565.001Stored Data Manipulation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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