ESTsecurity's ALYac antivirus program jams computers nationwide

ESTsecurity, a local cyber security company and creator of ALYac antivirus software, apologized Tuesday for jamming computers around the country due to an error in an update on Monday afternoon.

“We sincerely apologize for inconveniencing users with an issue in our ALYac anti-virus software,” the company wrote in a letter posted on the website. “We will come up with measures to prevent this from happening again and post the details on our website in September."

According to the company, after an update of ALYac at around 11:30 a.m. Monday, the program mistook codes in certain normal programs for malicious viruses. When users clicked the “report virus” pop-up, the computers froze.

Some computers ran normally after rebooting, but some continued to only show a blue screen even after rebooting, according to online posts. A fix was made at 11:30 p.m. and the company explained steps users can take if their computers remain jammed.

Only the free version for individual users was affected, not the enterprise version.

“We vow to thoroughly review our work environment and process so as to become a security solution company that provides a stable service,” ESTsecurity said.

ESTsecurity split off from ESTsoft in 2017, a software company founded in 1993. ALYac was developed in 2007 and has over 16 million users as of 2019.

BY YOON SO-YEON [yoon.soyeon@joongang.co.kr]