Medium severity · published Mar 27, 2026
CVE-2026-33205
calibre has Server-Side Request Forgery in ebook viewer backend
5.5
CVSS
0.2%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 7% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CA
calibre · kovidgoyal
< 9.6.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33205
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-33205
Exploit
https://github.com/kovidgoyal/calibre/security/advisories/GHSA-4926-v9px-wv7v
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