CVE-2026-55408 Koodo Reader: Remote code execution via malicious epub file
Attackers can execute arbitrary code via malicious EPUB files in Koodo Reader due to unsafe IPC handling and unsanitized HTML rendering.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-55408?
CVE-2026-55408 is a high-severity code injection vulnerability in koodo-reader, published on 7 Jul 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
Koodo Reader is an ebook reader. In version 2.3.0 and earlier, Koodo Reader is vulnerable to remote code execution through malicious EPUB files because the open-book IPC handler enables nodeIntegrationInSubFrames and EPUB chapter content is rendered with unsanitized innerHTML. An attacker can craft an EPUB book that, when imported and opened by the victim, instantiates a hidden iframe with Node.js API access and executes arbitrary operating system commands with the victim user's privileges. This issue is fixed in version 2.3.1.
Weakness: CWE-94
Which versions are affected by CVE-2026-55408?
How do I fix CVE-2026-55408?
No fix has been published for CVE-2026-55408 yet. Limit exposure of the affected software until one is available.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-55408 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55408 exists.
Sources
Also known as GHSA-mjr7-w4jq-2rq9.