Universal cross-site scripting in WebKitGTK+ and WPE WebKit - CVE-2026-86898
Published: September 15, 2026
Vulnerability identifier: #VU149924
CSH Severity: Medium
CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N]
CVE-ID: CVE-2026-86898
CWE-ID: CWE-79
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.
The vulnerability exists due to insufficient sanitization of user-supplied data. A remote attacker can trick the victim to open a specially crafted web archive and execute arbitrary HTML and script code in user's browser in context of vulnerable website.
Affected software
WebKitGTK+
WPE WebKit
Apple Safari
Apple iOS
iPadOS
macOS
WPE WebKit
Apple Safari
Apple iOS
iPadOS
macOS
How to mitigate CVE-2026-86898
Install updates from vendor's website.
Apple Safari - update to 27.0
Apple iOS - addressed in versions 27.0 24A427, 27.0 24A437
iPadOS - update to 27.0 24A437
macOS - update to 27.0 26A428
Apple iOS - addressed in versions 27.0 24A427, 27.0 24A437
iPadOS - update to 27.0 24A437
macOS - update to 27.0 26A428