CVE-2026-73248 — calibre: Bypass of Python template restrictions via nested `template()` leading to RCE
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…
Published: 2026-08-11 · CVSS: 8.5 · CVSS 4.0
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7