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CVE-2026-73248 (GCVE-0-2026-73248)

Vulnerability from cvelistv5 – Published: 2026-08-11 21:56 – Updated: 2026-08-12 13:52
VLAI
Title
calibre: Bypass of Python template restrictions via nested `template()` leading to RCE
Summary
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.
Severity
8.5 (High)
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
SSVC
Exploitation: poc Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-12 12:41 UTC
CWE
  • CWE-94 - Improper Control of Generation of Code ('Code Injection')
  • CWE-95 - Improper Neutralization of Directives in Dynamically Evaluated Code ('Eval Injection')
Assigner
References
Impacted products
Vendor Product Version CPE status
kovidgoyal calibre Affected: < 9.12.0
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
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  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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