Path Traversal in Calibre-Ebook Calibre
CVE-2026-33206
calibre is a cross-platform e-book manager for viewing, converting, editing, and cataloging e-books. Prior to version 9.6.0, a path traversal vulnerability exists in Calibre' handling of images in Markdown and other similar text-based files allowing an attacker to include arbitrary files from the file system into the converted book. Additionally, missing authentication and server-side request forgery in the background-image endpoint in the ebook reader web view allow the files to be exfiltrated without additional interaction. Version 9.6.0 contains a fix.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.3 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.002 (11.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 11th percentile — 11.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000
Affected products
- Calibre-Ebook Calibre
- Kovidgoyal Calibre — versions < 9.6.0
Weakness classification (CWE)
References
- github.com/kovidgoyal/calibre/security/advisories/GHSA-h3p4-m74f-43g6 (Exploit, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-33206?
- CVE-2026-33206 is a medium-severity vulnerability in Calibre-Ebook Calibre, classified under Relative Path Traversal. CVSS score: 6.3/10. Published 2026-03-27.
- How severe is CVE-2026-33206?
- Medium severity. CVSS v3 base score is 6.3 out of 10.