Barracuda Urges Changing — Not Patching — Its Electronic mail Safety Gateways – Krebs on Safety
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 e-mail safety home equipment in such a elementary method that they will not be safely up to date with software program fixes.
The Barracuda Electronic mail Safety Gateway (ESG) 900 equipment.
Campbell, Calif. based mostly Barracuda stated it employed incident response agency Mandiant on Could 18 after receiving studies about uncommon visitors originating from its Electronic mail Safety Gateway (ESG) units, that are designed to take a seat on the fringe of a company’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 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 immediately started urging its ESG clients to wholesale rip out and substitute — 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 suggestion presently is full substitute of the impacted ESG.”
In a press release, Barracuda stated will probably be offering the substitute product to impacted clients for free of charge, and that not all ESG home equipment have been compromised.
“No different Barracuda product, together with our SaaS e-mail options, have been impacted by this vulnerability,” the corporate stated. “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’ve no cause to imagine that the equipment has been compromised presently.”
However, the assertion says that “out of an abundance of warning and in furtherance of our containment technique, we advocate impacted clients substitute their compromised equipment.”
“As of June 8, 2023, roughly 5% of energetic ESG home equipment worldwide have proven any proof of recognized indicators of compromise because of the vulnerability,” the assertion continues. “Regardless of deployment of further patches based mostly on recognized IOCs, we proceed to see proof of ongoing malware exercise on a subset of the compromised home equipment. Due to this fact, we wish clients to switch any compromised equipment with a brand new unaffected gadget.”
Rapid7‘s Caitlin Condon known as this exceptional flip of occasions “pretty beautiful,” and stated there seem like roughly 11,000 susceptible ESG units nonetheless linked 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 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 units, and that proof of knowledge exfiltration was recognized on some methods.
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 e-mail for months.
Nicholas Weaver, a researcher at College of California, Berkeley’s International Computer Science Institute (ICSI), stated it’s doubtless that the malware was in a position to 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 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 knowledge extortion, it’s extra like a smash-and-grab. In the event that they’re going for knowledge ransoming, they’re encrypting the info itself — not the machines.”
Along with changing units, Barracuda says ESG clients also needs to rotate any credentials linked to the equipment(s), and examine for indicators of compromise courting again to no less than 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 concerning the incident, parts of which are actually excerpted above.