It’s not typically {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 electronic mail safety home equipment in such a elementary manner that they will now 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 Might 18 after receiving stories about uncommon visitors originating from its E mail Safety Gateway (ESG) gadgets, that are designed to sit down on the fringe of a company’s community and scan all incoming and outgoing electronic mail for malware.
On Might 19, Barracuda recognized that the malicious visitors was profiting from a beforehand unknown vulnerability in its ESG home equipment, and on Might 20 the corporate pushed a patch for the flaw to all affected home equipment (CVE-2023-2868).
In its safety advisory, Barracuda stated the vulnerability existed within the Barracuda software program element chargeable 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 instantly started urging its ESG clients to wholesale rip out and exchange — not patch — affected home equipment.
“Impacted ESG home equipment should be instantly changed no matter patch model stage,” the corporate’s advisory warned. “Barracuda’s advice at the moment is full substitute of the impacted ESG.”
Rapid7‘s Caitlin Condon referred to as this outstanding flip of occasions “pretty beautiful,” and stated there look like roughly 11,000 susceptible ESG gadgets nonetheless linked to the Web worldwide.
“The pivot from patch to whole substitute of affected gadgets is pretty beautiful and implies the malware the menace actors deployed someway achieves persistence at a low sufficient stage that even wiping the gadget 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 gadgets, and that proof of information exfiltration was recognized on some programs.
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 international cyberspies in all probability have been hoovering up all their electronic mail for months.
Nicholas Weaver, a researcher at College of California, Berkeley’s Worldwide Pc Science Institute (ICSI), stated it’s seemingly that the malware was capable of corrupt the underlying firmware that powers the ESG gadgets in some irreparable manner.
“One of many targets of malware is to be exhausting to take away, and this implies the malware compromised the firmware itself to make it actually exhausting 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 gadgets, Barracuda says ESG clients must also rotate any credentials linked to the equipment(s), and test for indicators of compromise relationship again to at the least October 2022 utilizing the community and endpoint indicators the corporate has launched publicly.
