Also, users can choose and select their own avatars for their profile pages. ICQ users are identified and distinguished from one another by UIN, or User Identification Numbers, distributed in sequential order.
The UIN was invented by Mirabilis, as the user name assigned to each user upon registration.
Since 2000 ICQ and AIM users are able to add each other to their contact list without the need for any external clients.
As a response to UIN theft or sale of attractive UINs, ICQ started to store email addresses previously associated with a UIN.
The founding company of ICQ, Mirabilis, was established in June 1996 by five Israelis: Yair Goldfinger, Sefi Vigiser, Amnon Amir, Arik Vardi, and Arik's father Yossi Vardi.
They recognized that many people were accessing the internet through non-UNIX operating systems, such as Microsoft Windows, and those users were unfamiliar with established chat technologies, e.g. The technology Mirabilis developed for ICQ was distributed free of charge.
Dirty COW is a privilege escalation vulnerability in the Linux kernel that came to light last year, in October 2016.
The vulnerability allows an attacker to elevate the privilege of attack code to "root" level and carry out malicious operations.
As of 2013, around half of ICQ’s users were using its mobile apps, and in 2014, the number of users began growing for the first time since the purchase.
The Dirty COW bug existed in the Linux kernel code for nine years, since 2007.
At the time of its discovery, Dirty COW was a zero-day and researchers said attackers used it against Linux servers. A few days later after its discovery, researchers found that Dirty COW could be used to root Android devices.
Eliav Moshe replaced Gilliam in 2009 and became ICQ's managing director.
While ICQ was displaced by AOL Instant Messenger, Google Talk, and other competitors in the U. and many other countries over the 2000s, it remained the most popular instant messaging network in Russian-speaking countries, and an important part of online culture.