CVE-2026-53511
Prior to 9.10.0, a malicious EPUB, OPF, or PDF file can execute arbitrary Python code when its metadata is read by calibre, including through Add books or Edit books, by embedding a custom column definition with a python: template in…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.15%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
calibre is an e-book manager. Prior to 9.10.0, a malicious EPUB, OPF, or PDF file can execute arbitrary Python code when its metadata is read by calibre, including through Add books or Edit books, by embedding a custom column definition with a python: template in calibre:user_metadata that is passed unsanitized to exec() in the template formatter. This issue is fixed in version 9.10.0.
- CVSS 4.0
- 8.5 HIGHCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.15% probability · 5th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-94
- Source
- security-advisories@github.com
References
- https://github.com/kovidgoyal/calibre/commit/712f4e1ff5c1e798c335bef3bacc4efdee052e9c
- https://github.com/kovidgoyal/calibre/releases/tag/v9.10.0
- https://github.com/kovidgoyal/calibre/security/advisories/GHSA-2j4m-2q7x-2c47
- https://lists.debian.org/debian-lts-announce/2026/08/msg00034.html
- https://github.com/kovidgoyal/calibre/security/advisories/GHSA-2j4m-2q7x-2c47
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.