What’s Vulnerable › Vulnerabilities

CVE-2021-3768: Cross-site Scripting (XSS) - Stored in bookstackapp/bookstack

• Severity: medium (CVSS 5.4 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.6% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2021-09-06 · updated 2026-06-17
• Weakness: CWE-79

Description

bookstack is vulnerable to Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Affected products

• bookstackapp/bookstack: before 21.08.2 — fixed in 21.08.2

How to fix

Upgrade to a fixed version: bookstackapp/bookstack 21.08.2. Check the vendor advisory for mitigations.

References

• https://github.com/bookstackapp/bookstack/commit/5e6092aaf8fd420202016038286554860bf8ea64
• https://huntr.dev/bounties/64a0229f-ff5e-4c64-b83e-9bfc0698a78e
• https://github.com/bookstackapp/bookstack/commit/5e6092aaf8fd420202016038286554860bf8ea64
• https://huntr.dev/bounties/64a0229f-ff5e-4c64-b83e-9bfc0698a78e

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