CVE-2026-73248

high

Description

calibre is an e-book manager. Prior to 9.12.0, calibre processes attacker-controlled composite_template metadata from a malicious EPUB, OPF, PDF, or similar file through program: and a nested template() call whose formatter does not inherit allow_python_templates=False, allowing a nested python: template to reach compile_python_template and execute arbitrary Python code when the file is opened or imported. This issue is fixed in version 9.12.0.

References

https://github.com/kovidgoyal/calibre/security/advisories/GHSA-4f7g-rjfp-hmvx

https://github.com/kovidgoyal/calibre/releases/tag/v9.12.0

https://github.com/kovidgoyal/calibre/commit/dac9990458374a81a5372a768bba6527d965aac8

Details

Source: Mitre, NVD

Published: 2026-08-11

Updated: 2026-08-11

Risk Information

CVSS v2

Base Score: 6.8

Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:P

Severity: Medium

CVSS v3

Base Score: 7.8

Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Severity: High

CVSS v4

Base Score: 8.5

Vector: 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

Severity: High