CVE Vulnerabilities

CVE-2021-41848

Use of Hard-coded Credentials

Published: Mar 11, 2022 | Modified: Nov 21, 2024
CVSS 3.x
7.8
HIGH
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS 2.x
7.2 HIGH
AV:L/AC:L/Au:N/C:C/I:C/A:C
RedHat/V2
RedHat/V3
Ubuntu

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.

Weakness

The product contains hard-coded credentials, such as a password or cryptographic key.

Affected Software

Name Vendor Start Version End Version
G90_firmware Bluproducts - (including) - (including)

Extended Description

There are two main variations:

Potential Mitigations

  • For outbound authentication: store passwords, keys, and other credentials outside of the code in a strongly-protected, encrypted configuration file or database that is protected from access by all outsiders, including other local users on the same system. Properly protect the key (CWE-320). If you cannot use encryption to protect the file, then make sure that the permissions are as restrictive as possible [REF-7].
  • In Windows environments, the Encrypted File System (EFS) may provide some protection.
  • For inbound authentication using passwords: apply strong one-way hashes to passwords and store those hashes in a configuration file or database with appropriate access control. That way, theft of the file/database still requires the attacker to try to crack the password. When handling an incoming password during authentication, take the hash of the password and compare it to the saved hash.
  • Use randomly assigned salts for each separate hash that is generated. This increases the amount of computation that an attacker needs to conduct a brute-force attack, possibly limiting the effectiveness of the rainbow table method.
  • For front-end to back-end connections: Three solutions are possible, although none are complete.

References