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TI-2026-25626 Aliases CVE-2026-33205

calibre has Server-Side Request Forgery in ebook viewer backend

Priority LOW 21CWE-918Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Passive
Attack complexity
Low
Attack requirements
None
Impact type
Information disclosure
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-918 and the CVSS impact.

Summary

calibre is a cross-platform e-book manager for viewing, converting, editing, and cataloging e-books. Prior to version 9.6.0, a Server-Side Request Forgery vulnerability in the background-image endpoint of calibre e-book reader's web view allows an attacker to perform blind GET requests to arbitrary URLs and exfiltrate information out from the ebook sandbox. Version 9.6.0 patches the issue.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0018 7th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed calibre (kovidgoyal): 9.6.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
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 9.6.09.6.0Patch availableCNA
  • calibre Vendorkovidgoyal Affected before 9.6.0 Fixed in 9.6.0 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:calibre-ebook:calibre:*:*:*:*:*:*:*:*before 9.6.0VulnerableCalibre
  • cpe:2.3:a:calibre-ebook:calibre:*:*:*:*:*:*:*:* Versions before 9.6.0 Vulnerable ·Calibre

Remediation

  • Fix · CNA calibre (kovidgoyal) Fixed in 9.6.0

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-2026-33205

References

Exploit 1

  • 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-2026-51386 Missing authorization in kovidgoyal calibre CVSS 3.1HIGH 7.5
  • 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
See all 29 →

Sources

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