Answer in brief
CVE-2026-73248 records a Unknown severity vulnerability in calibre: Bypass of Python template restrictions via nested `template()` leading to RCE. The current sources do not mark it as known exploited. The current feed maps kovidgoyal/calibre (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps kovidgoyal/calibre (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| kovidgoyal/calibregeneric | < 9.12.0 | Not reported |
Published upstream
Aug 11, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 11, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 11, 2026
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.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-73248 records a Unknown severity vulnerability in calibre: Bypass of Python template restrictions via nested `template()` leading to RCE. The current sources do not mark it as known exploited. The current feed maps kovidgoyal/calibre (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps kovidgoyal/calibre (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| kovidgoyal/calibregeneric | < 9.12.0 | Not reported |
Published upstream
Aug 11, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 11, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 11, 2026
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.
Quoted source text, attributed separately from HOL analysis.