CVE-2026-109434
mediumFenrir Sleipnir Browser for Android before 3.9.0 contains a UI spoofing vulnerability that allows remote attackers to impersonate the browser's trusted address…
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.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N Affected products
Not reported by the source (unknown — not "none").
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
No vendor advisory or patch reference tagged by NVD. Check the references below.
References
- https://www.fenrir-inc.com/jp/news/2026/10/15/sleipnir-mobile-for-android-3-9-0/ disclosure@vulncheck.com
- https://www.vulncheck.com/advisories/sleipnir-browser-fullscreen-address-bar-spoofing disclosure@vulncheck.com
