CVE-2026-109434
Sleipnir Browser < 3.9.0 Fullscreen Address Bar Spoofing
CVSS Score
4.3
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-451 |
| Vendor | fenrir |
| Product | sleipnir mobile for android |
| Published | Oct 19, 2026 |
| Last Updated | Oct 19, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None
Affected Versions
Fenrir / Sleipnir Mobile for Android
0 < 3.9.0
References
Credits
Fanda Dwi Aprilianto