CVE-2026-25731
Calibre Affected by Arbitrary Code Execution via Server-Side Template Injection in Calibre HTML Export
Description
calibre is an e-book manager. Prior to 9.2.0, a Server-Side Template Injection (SSTI) vulnerability in Calibre's Templite templating engine allows arbitrary code execution when a user converts an ebook using a malicious custom template file via the --template-html or --template-html-index command-line options. This vulnerability is fixed in 9.2.0.
INFO
Published Date :
Feb. 6, 2026, 9:16 p.m.
Last Modified :
Feb. 17, 2026, 9:18 p.m.
Remotely Exploit :
No
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] |
Solution
- Update Calibre to version 9.2.0 or later.
- Avoid using malicious custom template files.
Public PoC/Exploit Available at Github
CVE-2026-25731 has a 3 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-25731.
| URL | Resource |
|---|---|
| https://github.com/kovidgoyal/calibre/commit/f0649b27512e987b95fcab2e1e0a3bcdafc23379 | Patch |
| https://github.com/kovidgoyal/calibre/security/advisories/GHSA-xrh9-w7qx-3gcc | ExploitThird Party Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-25731 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-25731
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Mirror of https://github.com/nomi-sec/PoC-in-GitHub
Proof of Concept for a Server-Side Template Injection (SSTI) vulnerability in Calibre’s Templite engine (GHSA-xrh9-w7qx-3gcc). Demonstrates arbitrary Python code execution via user-supplied HTML export templates in affected versions (≤ 9.1.0).
📡 PoC auto collect from GitHub. ⚠️ Be careful Malware.
security cve exploit poc vulnerability
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-25731 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-25731 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Feb. 17, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:calibre-ebook:calibre:*:*:*:*:*:*:*:* versions up to (excluding) 9.2.0 Added Reference Type GitHub, Inc.: https://github.com/kovidgoyal/calibre/commit/f0649b27512e987b95fcab2e1e0a3bcdafc23379 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/kovidgoyal/calibre/security/advisories/GHSA-xrh9-w7qx-3gcc Types: Exploit, Third Party Advisory -
New CVE Received by [email protected]
Feb. 06, 2026
Action Type Old Value New Value Added Description calibre is an e-book manager. Prior to 9.2.0, a Server-Side Template Injection (SSTI) vulnerability in Calibre's Templite templating engine allows arbitrary code execution when a user converts an ebook using a malicious custom template file via the --template-html or --template-html-index command-line options. This vulnerability is fixed in 9.2.0. Added CVSS V3.1 AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Added CWE CWE-1336 Added Reference https://github.com/kovidgoyal/calibre/commit/f0649b27512e987b95fcab2e1e0a3bcdafc23379 Added Reference https://github.com/kovidgoyal/calibre/security/advisories/GHSA-xrh9-w7qx-3gcc