Fenrir Sleipnir Browser for Android before 3.9.0 contains a UI spoofing vulnerability that allows remote attackers to impersonate the browser's trusted address bar by entering fullscreen mode via the Fullscreen API without displaying a persistent notification or trusted-origin indicator. Attackers can render a counterfeit address bar showing a trusted origin over attacker-controlled content after a single user tap, enabling credential harvesting, malware delivery, or social engineering through fake login, update, or payment pages.
History

Wed, 21 Oct 2026 17:15:00 +0000

Type Values Removed Values Added
First Time appeared Fenrir
Fenrir sleipnir Mobile For Android
Vendors & Products Fenrir
Fenrir sleipnir Mobile For Android

Mon, 19 Oct 2026 18:30:00 +0000

Type Values Removed Values Added
Description Fenrir Sleipnir Browser for Android before 3.9.0 contains a UI spoofing vulnerability that allows remote attackers to impersonate the browser's trusted address bar by entering fullscreen mode via the Fullscreen API without displaying a persistent notification or trusted-origin indicator. Attackers can render a counterfeit address bar showing a trusted origin over attacker-controlled content after a single user tap, enabling credential harvesting, malware delivery, or social engineering through fake login, update, or payment pages.
Title Sleipnir Browser < 3.9.0 Fullscreen Address Bar Spoofing
Weaknesses CWE-451
References
Metrics cvssV3_1

{'score': 4.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N'}

cvssV4_0

{'score': 5.1, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published: 2026-10-19T18:12:51.637Z

Updated: 2026-10-19T18:36:45.158Z

Reserved: 2026-10-12T15:52:36.682Z

Link: CVE-2026-109434

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Deferred

Published: 2026-10-19T19:17:19.650

Modified: 2026-10-19T21:14:14.150

Link: CVE-2026-109434

cve-icon Redhat

No data.