CVE-2021-41848: An issue was discovered in Luna Simo PPR1.180610.011/202001031830. It mishandles software updates such that local third-party apps can provide a spoof...

Description

An issue was discovered in Luna Simo PPR1.180610.011/202001031830. It mishandles software updates such that local third-party apps can provide a spoofed software update file that contains an arbitrary shell script and arbitrary ARM binary, where both will be executed as the root user with an SELinux domain named osi. To exploit this vulnerability, a local third-party app needs to have write access to external storage to write the spoofed update at the expected path. The vulnerable system binary (i.e., /system/bin/osi_bin) does not perform any authentication of the update file beyond ensuring that it is encrypted with an AES key (that is hard-coded in the vulnerable system binary). Processes executing with the osi SELinux domain can programmatically perform the following actions: install apps, grant runtime permissions to apps (including permissions with protection levels of dangerous and development), access extensive Personally Identifiable Information (PII) using the programmatically grant permissions, uninstall apps, set the default launcher app to a malicious launcher app that spoofs other apps, set a network proxy to intercept network traffic, unload kernel modules, set the default keyboard to a keyboard that has keylogging functionality, examine notification contents, send text messages, and more. The spoofed update can optionally contain an arbitrary ARM binary that will be locally stored in internal storage and executed at system startup to achieve persistent code execution as the root user with the osi SELinux domain. This ARM binary will continue to execute at startup even if the app that provided the spoofed update is uninstalled.

Metrics

CVSS 3.1

7.8/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

0.40%

32.2th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-798

Affected Software

Vendor	Product	Versions
Bluproducts	G90 Firmware	All versions
Bluproducts	G9 Firmware	All versions
Wikomobile	Tommy 3 Firmware	All versions
Wikomobile	Tommy 3 Plus Firmware	All versions
Luna	Simo Firmware	All versions

References

https://athack.com/session-details/401Third Party Advisory
https://simowireless.com/Vendor Advisory
https://www.kryptowire.com/android-firmware-2022/Broken Link
https://www.kryptowire.com/blog/vsim-vulnerability-within-simo-android-phones-exposed/Exploit, Third Party Advisory
https://athack.com/session-details/401Third Party Advisory
https://simowireless.com/Vendor Advisory
https://www.kryptowire.com/android-firmware-2022/Broken Link
https://www.kryptowire.com/blog/vsim-vulnerability-within-simo-android-phones-exposed/Exploit, Third Party Advisory

Timeline

Published: Mar 11, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-41848?

An issue was discovered in Luna Simo PPR1.180610.011/202001031830. It mishandles software updates such that local third-party apps can provide a spoofed software update file that contains an arbitrary shell script and arbitrary ARM binary, where both will be executed as the root user with an SELinux domain named osi. To exploit this vulnerability, a local third-party app needs to have write access to external storage to write the spoofed update at the expected path. The vulnerable system binary (i.e., /system/bin/osi_bin) does not perform any authentication of the update file beyond ensuring that it is encrypted with an AES key (that is hard-coded in the vulnerable system binary). Processes executing with the osi SELinux domain can programmatically perform the following actions: install apps, grant runtime permissions to apps (including permissions with protection levels of dangerous and development), access extensive Personally Identifiable Information (PII) using the programmatically grant permissions, uninstall apps, set the default launcher app to a malicious launcher app that spoofs other apps, set a network proxy to intercept network traffic, unload kernel modules, set the default keyboard to a keyboard that has keylogging functionality, examine notification contents, send text messages, and more. The spoofed update can optionally contain an arbitrary ARM binary that will be locally stored in internal storage and executed at system startup to achieve persistent code execution as the root user with the osi SELinux domain. This ARM binary will continue to execute at startup even if the app that provided the spoofed update is uninstalled.

How severe is CVE-2021-41848?

CVE-2021-41848 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 0.40% probability of exploitation in the next 30 days.

How do I fix CVE-2021-41848?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.