CVE-2019-16256 SIMalliance Toolbox Browser Command Injection Vulnerability
SIMalliance Toolbox Browser contains an command injection vulnerability that could allow remote attackers to retrieve location and IMEI information or execute a range of other attacks by modifying the attack message.
From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.
Should You Worry?
- CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 3 Nov 2021.
- Rated Critical severity (CVSS 9.8, scored by CISA).
- It has been in the catalogue for 1,829 days. Systems still unpatched now have almost certainly been scanned for it.
What It Is
Some Samsung devices include the SIMalliance Toolbox Browser (aka S@T Browser) on the UICC, which might allow remote attackers to retrieve location and IMEI information, or retrieve other data or execute certain commands, via SIM Toolkit (STK) instructions in an SMS message, aka Simjacker.
What To Do Now
- 1
Find it
Search your asset inventory and external attack surface for SIMalliance Toolbox Browser. Include cloud images, appliances and anything a supplier runs for you.
Attack Surface Management - 2
- 3
Hunt for compromise
If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.
Incident Response - 4
Prove it is fixed
Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.
Penetration Testing
Vendor Advisories
The Compliance Clock
General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.
More Exploited SIMalliance Flaws
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