April 16, 2024

It’s not usually {that a} zero-day vulnerability causes a community safety vendor to induce clients to bodily take away and decommission a whole line of affected {hardware} — versus simply making use of software program updates. However consultants say that’s precisely what transpired this week with Barracuda Networks, as the corporate struggled to fight a sprawling malware menace which seems to have undermined its e-mail safety home equipment in such a basic approach that they will not be safely up to date with software program fixes.

The Barracuda E-mail Safety Gateway (ESG) 900 equipment.

Campbell, Calif. primarily based Barracuda stated it employed incident response agency Mandiant on Could 18 after receiving stories about uncommon visitors originating from its E-mail Safety Gateway (ESG) units, that are designed to sit down on the fringe of a corporation’s community and scan all incoming and outgoing e-mail for malware.

On Could 19, Barracuda recognized that the malicious visitors was benefiting from a beforehand unknown vulnerability in its ESG home equipment, and on Could 20 the corporate pushed a patch for the flaw to all affected home equipment (CVE-2023-2868).

In its security advisory, Barracuda stated the vulnerability existed within the Barracuda software program part answerable for screening attachments for malware. Extra alarmingly, the corporate stated it seems attackers first began exploiting the flaw in October 2022.

However on June 6, Barracuda out of the blue started urging its ESG clients to wholesale rip out and change — not patch — affected home equipment.

“Impacted ESG home equipment have to be instantly changed no matter patch model stage,” the corporate’s advisory warned. “Barracuda’s advice presently is full alternative of the impacted ESG.”

Rapid7‘s Caitlin Condon referred to as this exceptional flip of occasions “pretty gorgeous,” and stated there seem like roughly 11,000 susceptible ESG units nonetheless related to the Web worldwide.

“The pivot from patch to complete alternative of affected units is pretty gorgeous and implies the malware the menace actors deployed one way or the other achieves persistence at a low sufficient stage that even wiping the machine wouldn’t eradicate attacker entry,” Condon wrote.

Barracuda stated the malware was recognized on a subset of home equipment that allowed the attackers persistent backdoor entry to the units, and that proof of knowledge exfiltration was recognized on some techniques.

Rapid7 stated it has seen no proof that attackers are utilizing the flaw to maneuver laterally inside sufferer networks. However that could be small comfort for Barracuda clients now coming to phrases with the notion that overseas cyberspies most likely have been hoovering up all their e-mail for months.

Nicholas Weaver, a researcher at College of California, Berkeley’s International Computer Science Institute (ICSI), stated it’s seemingly that the malware was in a position to corrupt the underlying firmware that powers the ESG units in some irreparable approach.

“One of many objectives of malware is to be onerous to take away, and this means the malware compromised the firmware itself to make it actually onerous to take away and actually stealthy,” Weaver stated. “That’s not a ransomware actor, that’s a state actor. Why? As a result of a ransomware actor doesn’t care about that stage of entry. They don’t want it. In the event that they’re going for information extortion, it’s extra like a smash-and-grab. In the event that they’re going for information ransoming, they’re encrypting the info itself — not the machines.”

Along with changing units, Barracuda says ESG clients also needs to rotate any credentials related to the equipment(s), and examine for indicators of compromise relationship again to a minimum of October 2022 utilizing the community and endpoint indicators the corporate has released publicly.