CVE-2026-82642 Readest: unsanitized iframe srcdoc attribute in the EPUB sanitizer can lead to arbitrary code execution
Attackers can execute arbitrary code via unsanitized iframe srcdoc attributes in EPUB files, bypassing DOMPurify restrictions in Readest.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2026-82642?
CVE-2026-82642 is a high-severity cross-site scripting vulnerability in readest, published on 30 Aug 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Readest is an open-source e-book reader built on Tauri. In versions prior to 0.11.16, EPUB chapter HTML is sanitized with DOMPurify using a configuration that forbade only the <script> tag (FORBID_TAGS: ['script']) in apps/readest-app/src/services/transformers/sanitizer.ts. DOMPurify does not parse the contents of the srcdoc attribute on <iframe> elements, treating it as an opaque string attribute, so an attacker who can get an <iframe> element to survive sanitization can embed a complete HTML document containing a <script> tag inside srcdoc and have it execute when the browser renders the iframe. The content iframe is configured with sandbox="allow-same-origin allow-scripts", so script executing inside it shares the parent origin and can reach parent.parent.__TAURI_INTERNALS__.invoke(...), giving access to every Tauri IPC command the application is permitted to use, which escalates to arbitrary code execution. The payload can be made invisible (zero-size, transparent iframe) so the reader sees only normal book text. Version 0.11.16 hardened the sanitizer configuration by adding 'iframe', 'object' and 'embed' to FORBID_TAGS and adding 'srcdoc' to FORBID_ATTR.
Weakness: CWE-79
Which versions are affected by CVE-2026-82642?
How do I fix CVE-2026-82642?
No fix has been published for CVE-2026-82642 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-82642 being exploited?
There is no known exploitation of CVE-2026-82642 in the wild and no public exploit code.
Sources
Also known as GHSA-p4x7-pf2c-xrvj, GHSA-wvmc-79x2-m97w.