# CVE-2026-30853: calibre: calibre is a cross-platform e-book manager for viewing, converting, editing, and cataloging e-books

CVE-2026-30853 is fixed in calibre on 1 platform, first by DEBIAN-CVE-2026-30853, released March 13, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-30853
- Priority: High
- CVSS: 8.2 (high)
- EPSS: 0.0019
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Mar 13, 2026

## Description

calibre is a cross-platform e-book manager for viewing, converting, editing, and cataloging e-books. Prior to 9.5.0, a path traversal vulnerability in the RocketBook (.rb) input plugin (src/calibre/ebooks/rb/reader.py) allows an attacker to write arbitrary files to any path writable by the calibre process when a user opens or converts a crafted .rb file. This is the same bug class fixed in CVE-2026-26065 for the PDB readers, but the fix was never applied to the RB reader. This vulnerability is fixed in 9.5.0.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | calibre Debian 12.15 (bookworm) | 6.13.0+repack-2+deb12u8 | [DEBIAN-CVE-2026-30853](https://patchblox.com/security/data/fix/linux/debian-cve-2026-30853.md) | Mar 13, 2026 |
| Linux | calibre Debian 13.5 (trixie) | 8.5.0+ds-1+deb13u3 | [DEBIAN-CVE-2026-30853](https://patchblox.com/security/data/fix/linux/debian-cve-2026-30853.md) | Mar 13, 2026 |
| Linux | calibre Debian 14 | 9.5.0+ds+~0.10.5-1 | [DEBIAN-CVE-2026-30853](https://patchblox.com/security/data/fix/linux/debian-cve-2026-30853.md) | Mar 13, 2026 |

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Data as of 2026-11-08T13:06:02Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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