Cross-site scripting in Twenty - CVE-2026-35451
Published: July 28, 2026
Vulnerability identifier: #VU139926
CSH Severity: Low
CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N]
CVE-ID: CVE-2026-35451
CWE-ID: CWE-79
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote user to execute arbitrary JavaScript in a victim's browser.
The vulnerability exists due to cross-site scripting in the BlockNote FileBlock component when rendering crafted file block content. A remote user can inject a javascript: URI into the url property of a file block to execute arbitrary JavaScript in a victim's browser.
User interaction is required to click on the malicious file attachment.
Affected software
Twenty
How to mitigate CVE-2026-35451
Install security update from vendor's website.
Twenty - update to 1.19.1