DEBIAN-CVE-2026-27824

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Source
https://security-tracker.debian.org/tracker/CVE-2026-27824
Import Source
https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-27824.json
JSON Data
https://api.osv.dev/v1/vulns/DEBIAN-CVE-2026-27824
Upstream
Published
2026-02-27T20:21:39Z
Modified
2026-09-14T17:03:01Z
Severity
  • 5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N CVSS Calculator
Summary
[none]
Details

calibre is a cross-platform e-book manager for viewing, converting, editing, and cataloging e-books. Prior to version 9.4.0, the calibre Content Server's brute-force protection mechanism uses a ban key derived from both remote_addr and the X-Forwarded-For header. Since the X-Forwarded-For header is read directly from the HTTP request without any validation or trusted-proxy configuration, an attacker can bypass IP-based bans by simply changing or adding this header, rendering the brute-force protection completely ineffective. This is particularly dangerous for calibre servers exposed to the internet, where brute-force protection is the primary defense against credential stuffing and password guessing attacks. Version 9.4.0 contains a fix for the issue.

References

Affected packages

Debian:12 / calibre

Package

Name
calibre
Purl
pkg:deb/debian/calibre?arch=source&distro=bookworm

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
6.13.0+repack-2+deb12u6

Affected versions

6.*
6.13.0+repack-2
6.13.0+repack-2+deb12u1
6.13.0+repack-2+deb12u2
6.13.0+repack-2+deb12u3
6.13.0+repack-2+deb12u4
6.13.0+repack-2+deb12u5

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-27824.json"

Debian:13 / calibre

Package

Name
calibre
Purl
pkg:deb/debian/calibre?arch=source&distro=trixie

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
8.5.0+ds-1+deb13u2

Affected versions

8.*
8.5.0+ds-1
8.5.0+ds-1+deb13u1

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-27824.json"

Debian:14 / calibre

Package

Name
calibre
Purl
pkg:deb/debian/calibre?arch=source&distro=forky

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
9.4.0+ds+~0.10.5-1

Affected versions

8.*
8.5.0+ds-1
8.6.0+ds-1
8.7.0+ds-1
8.8.0+ds-1
8.8.0+ds-2
8.8.0+ds-2+gcc15
8.8.0+ds-3
8.9.0+ds-1
8.9.0+ds-2
8.9.0+ds-3
8.9.0+ds-4
8.10.0+ds-1
8.10.0+ds-2
8.10.0+ds-3
8.11.0+ds+~0.10.5-1
8.11.1+ds+~0.10.5-1
8.11.1+ds+~0.10.5-2
8.11.1+ds+~0.10.5-3
8.12.0+ds+~0.10.5-1
8.13.0+ds+~0.10.5-1
8.13.0+ds+~0.10.5-2
8.13.0+ds+~0.10.5-3
8.14.0+ds+~0.10.5-1~bpo13+1
8.14.0+ds+~0.10.5-1
8.15.0+ds+~0.10.5-1~bpo13+1
8.15.0+ds+~0.10.5-1
8.15.0+ds+~0.10.5-2
8.16.0+ds+~0.10.5-1
8.16.0+ds+~0.10.5-2
8.16.1+ds+~0.10.5-1
8.16.2+ds+~0.10.5-1
8.16.2+ds+~0.10.5-2
8.16.2+ds+~0.10.5-3~bpo13+1
8.16.2+ds+~0.10.5-3
9.*
9.0.0+ds+~0.10.5-1
9.1.0+ds+~0.10.5-1
9.2.0+ds+~0.10.5-1
9.2.1+ds+~0.10.5-1
9.2.1+ds+~0.10.5-2
9.3.0+ds+~0.10.5-1
9.3.1+ds+~0.10.5-1

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-27824.json"