What is the CVSS score of CVE-2026-25731?

CVE-2026-25731 has a CVSS 3.1 base score of 7.8 (High). CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. EPSS exploitation probability: 0.0%.

Which versions of Calibre are affected by CVE-2026-25731?

CVE-2026-25731 is a high-severity vulnerability in Calibre e-book management software that could allow attackers to compromise systems where the application is installed.. A patch is available.

Is there a public PoC exploit available for CVE-2026-25731?

Yes, a public proof-of-concept exploit is available for CVE-2026-25731. Prioritise patching immediately. EPSS: 0.0%.

How to fix or mitigate CVE-2026-25731?

Within 24 hours: Identify all systems running Calibre and assess exposure scope. Within 7 days: Apply the available vendor patch to all affected instances and verify successful deployment. Within 30 days: Conduct post-patch validation and document remediation evidence for compliance records.

Calibre CVE-2026-25731

HIGH

Improper Neutralization of Special Elements Used in a Template Engine (CWE-1336)

2026-02-06 security-advisories@github.com

RCE Red Hat Calibre Suse Calibre Ebook

7.8

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

7.8 HIGH

AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

SUSE

HIGH

qualitative

Red Hat

7.8 HIGH

qualitative

Primary rating from GitHub Advisory.

CVSS VectorGitHub Advisory

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Lifecycle Timeline

Analysis Generated

Mar 12, 2026 - 21:54 vuln.today

PoC Detected

Feb 17, 2026 - 21:18 vuln.today

Public exploit code

Patch released

Feb 17, 2026 - 21:18 nvd

Patch available

CVE Published

Feb 06, 2026 - 21:16 nvd

HIGH 7.8

DescriptionGitHub Advisory

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.

AnalysisAI

calibre is an e-book manager. [CVSS 7.8 HIGH]

Technical ContextAI

Affects Calibre. 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.