EE is a British mobile network operator, internet service provider and It is the largest mobile network operator in the UK.
This critical vulnerability specificaly identified in EE’s 4G Mini WiFi modem access to the EE customer’s Laptop or PC and perform various malicios actions, inject the malware and exfiltrate the sensitive information.
This flow discovered by ZeroDayLab consultant Osanda Malith who is reported to the issue to EE and help them to release the patch for this critical vulnerability.
Major Vulnerability Discovered By ZeroDayLab | EE Local Privilege Escalation Vulnerability | EE 4G Mini WiFi modem customers more at risk of cyber attack. Read about the #vulnerability and steps EE customers must take: https://t.co/p8bXuduO5G #cybersecurity #infosec @osandamalith pic.twitter.com/THDm6nZmTM
— ZeroDayLab (@ZeroDayLab) September 20, 2018
How does a flaw Escalate the Privilege in WiFi Modem
Zerodaylab consultant who analyzed EE WiFi modem found that the unquoted service path vulnerability in its folders.
Basically, folder permissions never let anyone allows to directly write files but EE’s folder permission had been set to “Everyone:(OI)(CI)(F)”.
This permission allows any user can read, write, execute, create, delete do anything inside that folder and its subfolders.
When he analyzed the subfolders and find that ACL rules set as “OI – Object Inherit” and “CI – Container Inherit” which means that it’s subfolder also have full permission.
Since binary path name’s ServiceManager.exe windows executable, attackers can create a malicious program that posed as ServiceManager.exe and executing the binary as “NT AUTHORITYSYSTEM” which escalate privileges in a Windows operating system locally.
Video Demonstration shows the way attack exploit this vulnerability and gain the local privilege.
According to Zerodaylab, “an attacker can plant a reverse shell from a low privileged user account and by restarting the computer, the malicious service will be started as “NT AUTHORITYSYSTEM” by giving the attacker full system access to the remote PC.”
He was reported this vulnerability to Alcatel they have released a patch to update the modem and assigned CVE-2018-14327.