High 8.5Published Jul 7, 2026

CVE-2026-53511calibre: Arbitrary Code Execution in Template Formatter via Book Metadata

Updated under an hour ago (Oct 27, 2026, 9:00 PM ET)

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It affects kovidgoyal calibre. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for kovidgoyal calibre

Exploited in the last 30 days

calibre is an e-book manager. Prior to 9.10.0, a malicious EPUB, OPF, or PDF file can execute arbitrary Python code when its metadata is read by calibre, including through Add books or Edit books, by embedding a custom column definition with a python: template in calibre:user_metadata that is passed unsanitized to exec() in the template formatter. This issue is fixed in version 9.10.0.

CVSS: 8.5 HIGH (v4.0, CNA)CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Weakness (CWE): CWE-94
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Deferred
Record last updated: Aug 18, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

kovidgoyal calibre kovidgoyal:calibre (from the name)	before 9.10.0	CNA record

References

References

https://github.com/kovidgoyal/calibre/security/advisories/GHSA-2j4m-2q7x-2c47	x-refsource-confirm
https://github.com/kovidgoyal/calibre/commit/712f4e1ff5c1e798c335bef3bacc4efdee052e9c	x-refsource-misc
https://github.com/kovidgoyal/calibre/releases/tag/v9.10.0	x-refsource-misc
https://lists.debian.org/debian-lts-announce/2026/08/msg00034.html

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.