F-Secure Safe browser for Android vulnerable to Address Bar Spoofing

published 2021-08-11 5y ago modified 2026-06-17 4mo ago also EUVD-2021-20278

cvss: 3.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.1%; EPSS 1.1% chance of exploitation in 30 days, percentile 65%
public exploits: 0; none known

An address bar spoofing vulnerability was discovered in Safe Browser for Android. When user clicks on a specially crafted a malicious URL, it appears like a legitimate one on the address bar, while the content comes from other domain and presented in a window, covering the original content. A remote attacker can leverage this to perform address bar spoofing attack.

Patch / fix

fixed in 1

f-secure safe 18.4.0

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Exploit prediction

1.08% chance of exploitation in the next 30 days, higher than 65% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	3.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
NVD	3.1	3.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
NVD	2.0	3.5	AV:N/AC:M/Au:S/C:N/I:P/A:N

Affected products

F-Secure F-Secure Mobile Security

References

f-secure.com /en/business/programs/vulnerability-reward-program/hall-of-fame
vendor-advisory
f-secure.com /en/business/support-and-downloads/security-advisories
vendor-advisory
f-secure.com /en/business/support-and-downloads/security-advisories/cve-2021-33594
vendor-advisory

Sources

CVE List CVE-2021-33594
NVD CVE-2021-33594

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