Pro-Russian hacking group Killnet waged a cyberattack against US government websites, disrupting the websites of multiple US airports in denial-of-service (DDoS) attacks.

Killnet called on aligned groups to carry out DDoS attacks on US infrastructure, marking an escalating campaign protesting the US' proxy war with Russia in Ukraine. 

Los Angeles International Airport (LAX), Chicago O'Hare, Hartsfield-Jackson Atlanta International Airport, and the Indianapolis International Airport were some of the major airports affected by the DDoS. 

The attack rendered the websites inaccessible for hours, despite that they did not affect operations. 

Mandiant researchers detected a total of 15 airports' websites that have been disrupted.

LAX released an email statement confirming the attack: "Early this morning, the FlyLAX.com website was partially disrupted," adding that "No internal airport systems were compromised and there were no operational disruptions."

Killnet has asked its supporters to join in airport attacks on its Telegram channel, according to Ivan Righi, a senior cyber threat intelligence analyst. The group mentioned 49 websites across the US as possible targets. 

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"At this time, it is unknown how successful these attacks were, but Killnet attacks are known to take websites down for short periods," Righi says. 

Killnet, upon attacking Chicago O'Hare first, stated its motivation to target the US civilian network sector. 

Last week, Killnet claimed responsibility for the attacks on government websites in Mississippi, Kentucky and Colorado, in addition to attacking US Congress websites, disrupting services for a short period of time. 

In August, Killnet announced its plan to attack Lockheed Martin, which manufactures the HIMARS rocket launchers being used in the war in Ukraine. 

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