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 compositetemplate metadata from a malicious EPUB, OPF, PDF, or similar file through program: and a nested template call whose formatter does not inherit allowpythontemplates=False, allowing a nested python:...

CVE-2026-73248

calibre is an e-book manager. Prior to 9.12.0, calibre processes attacker-controlled compositetemplate metadata from a malicious EPUB, OPF, PDF, or similar file through program: and a nested template call whose formatter does not inherit allowpythontemplates=False, allowing a nested python:...