Reverse Tabnabbing in HFS - #VU127491
Published: April 24, 2026
Vulnerability identifier: #VU127491
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: N/A
CWE-ID: CWE-1022
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: rejetto
Affected software:
HFS
HFS
Detailed vulnerability description
The vulnerability allows a remote attacker to conduct phishing attacks.
The vulnerability exists due to use of web link to untrusted target with window.opener access in the HFS web link feature when opening an added external web link in a new tab. A remote attacker can compromise or control the linked external page to replace the original HFS tab with a phishing page to conduct phishing attacks.
Only users on browsers without the browser-level protection remain vulnerable.
Remediation
Install security update from vendor's website.