Barracuda Urges Changing — Not Patching — Its E-mail Safety Gateways – Krebs on Safety

It’s not usually {that a} zero-day vulnerability causes a community safety vendor to induce prospects 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 method that they’ll not be safely up to date with software program fixes.

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

Campbell, Calif. primarily based Barracuda mentioned it employed incident response agency Mandiant on Might 18 after receiving reviews about uncommon site 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 Might 19, Barracuda recognized that the malicious site visitors was benefiting 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 security advisory, Barracuda mentioned the vulnerability existed within the Barracuda software program part liable for screening attachments for malware. Extra alarmingly, the corporate mentioned it seems attackers first began exploiting the flaw in October 2022.

However on June 6, Barracuda out of the blue started urging its ESG prospects 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 right now is full substitute of the impacted ESG.”

In an announcement, Barracuda mentioned it will likely be offering the substitute product to impacted prospects for gratis, and that not all ESG home equipment had been compromised.

“No different Barracuda product, together with our SaaS e mail options, had been impacted by this vulnerability,” the corporate mentioned. “If an ESG equipment is displaying a notification within the Consumer Interface, the ESG equipment had indicators of compromise. If no notification is displayed, we have now no motive to imagine that the equipment has been compromised right now.”

Nonetheless, the assertion says that “out of an abundance of warning and in furtherance of our containment technique, we advocate impacted prospects change their compromised equipment.”

“As of June 8, 2023, roughly 5% of lively ESG home equipment worldwide have proven any proof of recognized indicators of compromise as a result of vulnerability,” the assertion continues. “Regardless of deployment of extra patches primarily based on recognized IOCs, we proceed to see proof of ongoing malware exercise on a subset of the compromised home equipment. Subsequently, we wish prospects to interchange any compromised equipment with a brand new unaffected system.”

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

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

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

Rapid7 mentioned 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 prospects now coming to phrases with the notion that international 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), mentioned it’s doubtless that the malware was capable of corrupt the underlying firmware that powers the ESG units in some irreparable method.

“One of many objectives of malware is to be laborious to take away, and this means the malware compromised the firmware itself to make it actually laborious to take away and actually stealthy,” Weaver mentioned. “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 information itself — not the machines.”

Along with changing units, Barracuda says ESG prospects also needs to rotate any credentials related to the equipment(s), and verify for indicators of compromise courting again to at the very least October 2022 utilizing the community and endpoint indicators the corporate has released publicly.

Replace, June 9, 11:55 a.m. ET: Barracuda has issued an up to date assertion in regards to the incident, parts of which are actually excerpted above.