CVE-2020-26297: XSS in mdBook's search page

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-01-04 · updated 2026-06-17
Weakness: CWE-79

Description

mdBook is a utility to create modern online books from Markdown files and is written in Rust. In mdBook before version 0.4.5, there is a vulnerability affecting the search feature of mdBook, which could allow an attacker to execute arbitrary JavaScript code on the page. The search feature of mdBook (introduced in version 0.1.4) was affected by a cross site scripting vulnerability that allowed an attacker to execute arbitrary JavaScript code on an user's browser by tricking the user into typing a malicious search query, or tricking the user into clicking a link to the search page with the malicious search query prefilled. mdBook 0.4.5 fixes the vulnerability by properly escaping the search query. Owners of websites built with mdBook have to upgrade to mdBook 0.4.5 or greater and rebuild their website contents with it.

Affected products

rust-lang mdBook: from 0.1.4 before 0.4.5 — fixed in 0.4.5
Crates.Io Mdbook: from 0.1.4-0 before 0.4.5 — fixed in 0.4.5

How to fix

Upgrade to a fixed version: rust-lang mdBook 0.4.5; Crates.Io Mdbook 0.4.5. Check the vendor advisory for mitigations.

References

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