CVE-2021-44751F-Secure SAFE Browser vulnerable to USSD attacks
- 4.3MediumCVSS base score
- 0.57%Exploitation in 30 daysEPSS · top 52% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
A vulnerability affecting F-Secure SAFE browser was discovered. A maliciously crafted website attached with USSD code in JavaScript or iFrame can trigger dialer application from F-Secure browser which can be exploited by an attacker to send unwanted USSD messages or perform unwanted calls. In most modern Android OS, dialer application will require user interaction, however, some older Android OS may not need user interaction.
Timeline
ID reserved
By F-SecureUS
- 4 months later
· 4 months later
Published
- 2 years later
· 2 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| F-SecureUSCNA (assigner) | 3.1 | Medium4.3 | CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:L/I:L/A:L |
| NVDNVD · Modified | 3.1 | Medium5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.57% · top 52% of all CVEs (12 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.3.
Affected products
F-Secure · F-Secure SAFE Browser for Android Version 18.5 & below
- affected 18.5 – < 18.6
What to do
Solution: FIX : A fix has been released in the automatic update channel since 22nd, March 2022. No user action is required.
References
References1
- https://www.f-secure.com/en/business/programs/vulnerability-reward-program/hall-of-fame (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2021-31566 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2021-44751)Record last updated .