Is CVE-2026-27810 in the CISA KEV catalog?

No. CVE-2026-27810 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2026-27810?

CVE-2026-27810 has a CVSS v3 base score of 6.4 (MEDIUM).

What is the EPSS score for CVE-2026-27810?

CVE-2026-27810 has an EPSS score of 0.21% (11th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2026-27810?

Upgrade calibre on debian 12 to 6.13.0+repack-2+deb12u6 or later. Fixes are available for 2 affected products.

CVE & CISA-KEV Catalog

CVE-2026-27810

MEDIUM

6.4

CVSS v3

NVD

Description

calibre is a cross-platform e-book manager for viewing, converting, editing, and cataloging e-books. Prior to version 9.4.0, an HTTP Response Header Injection vulnerability in the calibre Content Server allows any authenticated user to inject arbitrary HTTP headers into server responses via an unsanitized `content_disposition` query parameter in the `/get/` and `/data-files/get/` endpoints. All users running the calibre Content Server with authentication enabled are affected. The vulnerability is exploitable by any authenticated user and can also be triggered by tricking an authenticated victim into clicking a crafted link. Version 9.4.0 contains a fix for the issue.

CWE-113

How to fix

Remediation Available

calibreDebian

Fixed in:6.13.0+repack-2+deb12u6CVE-2026-27810

Fixed in:8.5.0+ds-1+deb13u2CVE-2026-27810

Fixed in:9.4.0+ds+~0.10.5-1CVE-2026-27810

calibreWindows application

Affected:9.4.0Fixed in:9.4.0Kovid Goyal

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredLow

User InteractionNone

ScopeChanged

Impact

ConfidentialityLow

IntegrityLow

AvailabilityNone

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

Exploit Intelligence

0.21%probability of exploitation in 30 days

11thpercentile

Low risk: more likely to be exploited than 11% of all known CVEs.

References

Exploit1

github.com

Embed a live status badge for CVE-2026-27810

Markdown

[![CVE-2026-27810](https://tridentstack.com/cve/badge/CVE-2026-27810.svg)](https://tridentstack.com/cve/CVE-2026-27810)

HTML

<a href="https://tridentstack.com/cve/CVE-2026-27810"><img src="https://tridentstack.com/cve/badge/CVE-2026-27810.svg" alt="CVE-2026-27810"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

Start free

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-03-04.