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.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| kovidgoyal | calibre | < 9.4.0 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | calibre | 9.4.0+ds+~0.10.5-1 | — |
| Debian 13 | calibre | 8.5.0+ds-1+deb13u2 | — |
| Debian 12 | calibre | 6.13.0+repack-2+deb12u6 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | calibre | No fix yet | — |
| Ubuntu 26.04 LTS | calibre | No fix yet | — |
| Ubuntu 25.10 | calibre | No fix yet | — |
| Ubuntu 24.04 LTS | calibre | No fix yet | — |
| Ubuntu 22.04 LTS | calibre | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | calibre | No fix yet | — |
| Ubuntu 18.04 LTS | calibre | No fix yet | — |
| Ubuntu 16.04 LTS | calibre | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | calibre | 9.7.0-1.1 | openSUSE-SU-2026:10587-1 |
Advisories 1
- openSUSE-SU-2026:10587-1 calibre-9.7.0-1.1 on GA media SUSE / openSUSE Security Updates · Apr 22, 2026