CVE-2026-53511
calibre: Arbitrary Code Execution in Template Formatter via Book Metadata
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
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.
Public exploit
A reference of the record is tagged as an exploit or proof of concept: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: a proof of concept is public.
- https://github.com/kovidgoyal/calibre/security/advisories/GHSA-2j4m-2q7x-2c47 (opens in a new tab)x_refsource_CONFIRMexploit
Timeline
ID reserved
By GitHub_M
- 28 days later
· 28 days later
Published
- 42 days later
· 42 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 4.0 | High8.5 | 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 |
| NVDNVD · Deferred | 4.0 | High8.5 | 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.22% · top 87% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.5.
Weakness
Affected products
- affected < 9.10.0
References (4)
- https://github.com/kovidgoyal/calibre/security/advisories/GHSA-2j4m-2q7x-2c47 (opens in a new tab)x_refsource_CONFIRMexploit
- https://github.com/kovidgoyal/calibre/commit/712f4e1ff5c1e798c335bef3bacc4efdee052e9c (opens in a new tab)x_refsource_MISC
- https://github.com/kovidgoyal/calibre/releases/tag/v9.10.0 (opens in a new tab)x_refsource_MISC
- https://lists.debian.org/debian-lts-announce/2026/08/msg00034.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-53511)Record last updated .