Security Unlocked 5.19.21
Ep 28 | 5.19.21

Contact Us; Phish You!


Nic Fillingham: Hello and welcome to Security Unlocked, a new podcast from Microsoft where we unlock insights from the latest in news and research from across Microsoft security, engineering and operations teams. I'm Nick Fillingham.

Natalia Godyla: And I'm Natalia Godyla. In each episode we'll discuss the latest stories from Microsoft Security, deep dive into the newest threat intel, research, and data science.

Nic Fillingham: And profile some of the fascinating people working on artificial intelligence in Microsoft Security.

Natalia Godyla: And now, let's unlock the pod.

Nic Fillingham: Hello, the internet. Hello, listeners. Welcome to episode 28 of Security Unlocked. Nic and Natalia back with you once again for a, a regular, uh, episode of the podcast. Natalia, how are you?

Natalia Godyla: Hi, Nic. I'm doing well. I'm stoked to have Emily Hacker, a threat analyst at Microsoft back on the show today.

Nic Fillingham: Yes, Emily is back on the podcast discussing a blog that she co-authored with Justin Carroll, another return champ here on the podcast, called Investigating a Unique Form of Email Delivery for IcedID Malware, the emphasis is on form was, uh, due to the sort of word play there. That's from April 9th. Natalia, TLDR, here. What's, what's Emily talking about in this blog?

Natalia Godyla: In this blog she's talking about how attackers are delivering IcedID malware through websites contact submission forms by impersonating artists who claim that the companies use their artwork illegally. It's a new take targeting the person managing the submission form.

Nic Fillingham: Yeah, it's fascinating. The attackers here don't need to go and, you know, buy or steal email lists. They don't need to spin up, uh, you know, any e- email infrastructure or get access to botnets. They're, they're really just finding websites that have a contact as form. Many do, and they are evading CAPTCHA here, and we talk about that with, with, with, uh, Emily about they're somehow getting around the, the CAPTCHA technology to try and weed out automation. But they are getting around that which sort of an interesting part of the conversation.

Nic Fillingham: Before we get into that conversation, though, a reminder to Security Unlock listeners that we have a new podcast. We just launched a new podcast in partnership with the CyberWire. It is Security Unlocked: CISO Series with Bret Arsenault. Bret Arsenault is the chief information security officer, the CISO, for Microsoft, and we've partnered with him and his team, uh, as well as the CyberWire, to create a brand new podcast series where Bret gets to chat with security and technology leaders at Microsoft as well as some of his CISO peers across the industry. Fantastic conversations into some of the biggest challenges in cyber security today, some of the strategies that these big, big organizations are, are undertaking, including Microsoft, and some practical guidance that really is gonna mirror the things that are being done by security teams here at Microsoft and are some of Microsoft's biggest customers.

Nic Fillingham: So, I urge you all to, uh, go check that one out. You can find it at the CyberWire. You can also go to, and that's CISO as in C-I-S-O. CISO or CISO, if you're across the pond,, but for now, on with the pod.

Natalia Godyla: On with the pod.

Nic Fillingham: Welcome back to the Security Unlocked Podcast. Emily Hacker, thanks for joining us.

Emily Hacker: Thank you for having me again.

Nic Fillingham: Emily, you are, uh, coming back to the podcast. You're a returning champion. Uh, this is, I think your, your second appearance and you're here-

Emily Hacker: Yes, it is.

Nic Fillingham: ... on behalf of your colleague, uh, Justin Carroll, who has, has also been on multiple times. The two of you collaborated on a blog post from April the 9th, 2021, called Investigating a Unique Form-

Emily Hacker: (laughs)

Nic Fillingham: ... in, uh, "Form", of email delivery for IcedID malware. The form bit is a pun, is a play on words.

Emily Hacker: Mm-hmm (affirmative).

Nic Fillingham: I- is it not?

Emily Hacker: Oh, it definitely is. Yeah.

Nic Fillingham: (laughs) I'm glad I picked up on that, which is a, you know, fascinating, uh, campaign that you've uncovered, the two of you uncovered and you wrote about it on the blog post. Before we jump into that, quick recap, please, if you could just reintroduce yourself to the audience. Uh, what, what do you do? What's your day-to-day look like? Who do you work with?

Emily Hacker: Yeah, definitely. So, I am a threat intelligence analyst, and I'm on the Threat Intelligence Global Engagement and Response team here at Microsoft. And, I am specifically focused on mostly email-based threats, and, as you mentioned on this blog I collaborate with my coworker, Justin Carroll, who is more specifically focused on end-point threats, which is why we collaborated on this particular blog and the particular investigation, because it has both aspects. So, I spend a lot of my time investigating both credential phishing, but also malicious emails that are delivering malware, such as the ones in this case. And also business email, compromise type scam emails.

Nic Fillingham: Got it. And so readers of the Microsoft Security Blog, listeners of Security Unlocked Podcast will know that on a regular basis, your team, and then other, uh, threat intelligence teams from across Microsoft, will publish their findings of, of new campaigns and new techniques on the blog. And then we, we try and bring those authors onto the podcast to tell us about what they found that's what's happened in this blog. Um, the two of you uncovered a new, a unique way of attackers to deliver the IcedID malware. Can you walk us through this, this campaign and this technique that you, you both uncovered?

Emily Hacker: Yeah, definitely. So this one was really fun because as I mentioned, it evolved both email and endpoint. So this one was, as you mentioned, it was delivering IcedID. So we initially found the IcedID on the endpoint and looking at how this was getting onto various endpoints. We identified that it was coming from Outlook, which means it's coming from email. So we can't see too much in terms of the email itself from the endpoint, we can just see that it came from Outlook, but given the network connections that the affected machines were making directly after accessing Outlook, I was able to find the emails in our system that contains emails that have been submitted by user 'cause either reported to junk or reported as phish or reported as a false positive, if they think it's not a phish. And so that's where I was actually able to see the email itself and determined that there was some nefarious activity going on here.

Emily Hacker: So the emails in this case were really interesting in that they're not actually the attacker sending an email to a victim, which is what we normally see. So normally the attacker will either, you know, compromise a bunch of senders and send out emails that way, which is what we've seen a lot in a lot of other malware or they'll create their own attacker infrastructure and send emails directly that way. In this case, the attackers were abusing the contact forms on the websites. So if you are visiting a company's website and you're trying to contact them a lot of times, they're not going to just have a page where they offer up their emails or their phone numbers. And you have to fill in that form, which feels like it goes into the void sometimes. And you don't actually know who it went to in this case, the, the attackers were abusing hundreds of these contact forms, not just targeting any specific company.

Emily Hacker: And another thing that was unique about this is that for some of the affected companies that we had observed, I went and looked at their websites and their contact form does require a CAPTCHA. So it does appear that the attackers in this case have automated the filling out of these contact forms. And that they've automated a way around these CAPTCHAs, just given the, the sheer volume of these emails I'm seeing. This is a good way of doing this because for the attacker, this is a much more high fidelity method of contacting these companies because they don't have to worry about having an incorrect email address if they have gotten a list off of like Pastebin or a list, you know, they purchased a list perhaps from another criminal.

Emily Hacker: A lot of times in those cases, if they're emailing directly, there's gonna be some, some false emails in those lists that just don't get delivered. With the contact form, they're designed to be delivered. So it's gonna give the attacker a higher chance of success in terms of being delivered to a real inbox.

Natalia Godyla: And so when we, we talk about the progression of the attack, they're automating this process of submitting to these contact forms. What are they submitting in the form? What is the, and what is the end goal? So there's malware somewhere in their-

Emily Hacker: Mh-mm-hmm (affirmative).

Natalia Godyla: ... response. What next?

Emily Hacker: Yeah. It's a really good question. So the emails or rather the contact form submissions themselves, they're all containing a, a lore. So the contents themselves are lore that the attacker is pretending to be a, um, artist, a photographer, and illustrator, something along those lines. There's a handful of different jobs that they're pretending to be. And they are claiming that the company that they are contacting has used an image that belongs to the artist, illustrator, photographer on their website without permission. And so the attacker is saying, "You used my art without permission. I'm going to sue you if you don't take this down, if you wanna know what aren't talking about, click on this link and it'll show you the exact art that I'm talking about or the exact photo." What have you, all of the emails were virtually identical in terms of the content and the lore.

Emily Hacker: The attacker was using a bunch of different fake emails. So when you fill out a contact form, you have to put your email so the, the company can contact you, I guess, in reply, if they need to. And the attackers, almost every single email that I looked at had a different fake attacker email, but they did all follow a really consistent pattern in terms of the, the name, Mel and variations on that name. So they had like Melanie, I saw like Molina, like I said, there was hundreds of them. So the email would be Mel and then something relating to photography or illustration or art, just to add a little bit more credence, I think to their, to their lore. It made it look like the email address was actually associated with a real photographer. The, the attacker had no need to actually register or create any of those emails because they weren't sending from those emails. They were sending from the contact form. So it made it a lot easier for the attacker to appear legitimate without having to go through the trouble of creating legitimate emails.

Emily Hacker: And then the, um, the email itself from the recipients view would appear other than the fact that it felt fishy, at least to me, but, you know, I literally do this for a living. So maybe just everything feels fishy to me. Other than that, the email itself is going to appear totally legitimate because since it's coming through the contact form, it's not going to be from an email address. They don't recognize because a lot of times these contact forms are set up in a way where it'll send from the recipient's domain. So for example, a contact form, I don't know if this is how this works, but just as an example at Microsoft might actually send from or the other large percentage of these that I saw were sent from the contact form hosting provider. So there are a lot of providers that host is kind of content for companies. And so the emails would be coming from those known email addresses and the emails themselves are gonna contain all of the expected fields, all in all. It's basically a legitimate email other than the fact that it's malicious.

Nic Fillingham: And, and just reading through the sample email that you, that you have in the blog post here, like sort of grammatically speaking it's, it reads very legitimately like, the-

Emily Hacker: Mh-mm-hmm (affirmative).

Nic Fillingham: ... you know, the s- the, the grammar and the spelling is, it's colloquial, but it's, but it seems, you know, pretty legitimate. The idea of a photographer, a freelance photographer, stumbling upon their images being used without permission. You know, you hear stories of that happening. That seems to be somewhat plausible, not knowing how to contact the, the infringing organization. And then therefore going to the generic contact us form like this all, this all seems quite plausible.

Emily Hacker: And, definitely. And it's als one of those situations where even though, like I said, I do this for a living, so I read this and I was like, there's no way that's legit. But if my job was to be responsible for that email inbox, where stuff like this came in, it would be hard for me to weigh the consequences of like, is it more likely that this is like a malicious email? Or is it yeah. Is it possible that this is legit? And if I ignore it, my company is gonna get sued. Like, I feel like that kind of would give the recipient that, that weird spot of being like, "I don't want to infect the company with malware, or, you know, I don't wanna click on a phishing link if that's what this is, but also if I don't and then we get sued, is it my fault?"

Emily Hacker: I just, I, I feel for the recipient. So I, I understand why people would be clicking on this one and infecting themselves. And speaking of clicking on that is the other thing that's included in this email. So that was the last bit of this email that turns us from just being weird/legitimate, to totally malicious. All of the emails contain a link. And, um, the links themselves are also abusing legitimate infrastructure. So that's, uh, the next bit of abused, legitimate infrastructure that just adds that next bit of like believability if that's a word to this campaign.

Nic Fillingham: It is a word.

Emily Hacker: Okay, good believability. Is that the, the links, you know, we're, if you don't work insecurity, and even if you do work in security, we're all kind of trained like, "Oh, check the links, hover over the links and make sure it's going somewhere that you expect and make sure it's not going to like bad site dot bad, dot bad or something," you know, but these don't do that. All of the emails contained a link. And I've looked at literally hundreds of these, and they all contain, um, a different URL, but the same domain. If you click on the link, when you receive the email, it'll take you actually to a legitimate Google authentication page that'll ask you to log in with your Google credentials, which again, every step along the way of this, of the email portion of this, of this attack, the attacker just took extra steps to make it seem as real as possible, or to almost like every piece of security advice.

Emily Hacker: I feel like they did that thing. So it seemed more legitimate because it's not a phishing page. It's not like a fake Google page that's stealing your credentials. It's a real where you would log in with your real Google credentials. Another thing that this does outside of just adding an air of legitimacy to the emails, it also can make it difficult for some security automation products. So a product that would be looking at emails and detonating the link to see if they're malicious and this case, it would detonate the link and it would land on, you know, a real Google authentication page. And in some cases it may not be able to authenticate. And then it would just mark these as good, because it would see what it expected to see. So, outside of just seeming legit, it also makes, you know, security products make this think it's more legit as well. But from there, the, uh, user would be redirected through a series of attacker own domains and would eventually download a zip file, which if they unzipped, they would find the IcedID payload.

Emily Hacker: So in this case, it's delivering IcedID, although this technique could be used to deliver other stuff as well, but it's not necessarily surprising that it's delivering IcedID right now, because pretty much everything I feel like I'm seeing lately as I study. And I don't think I'm alone in that there's murmurings that IcedID might be replacing Emotets now that you Emotet has been taken down in terms of being, you know, the annoyingly present malware. (laughs) So this is just one of many delivery methods that we've seen for IcedID malware lately. It's certainly in my opinion, one of the more interesting ones, because in the past, we've seen IcedID delivered a lot via email, but, um, just delivered via, you know, the normal type of malicious email if you will, with a compromised email sending with a, a zip attachment, this is much more interesting.

Emily Hacker: But in this case, if the user downloaded the payload, the payload would actually do many things. So in this case, it was looking for machine information. It was looking to see what kind of security tools were in place to see what kind of antivirus the machine was running. It was getting IP and system information. It was getting, you know, domain information and also looking to access credentials that might be stored in your browser. And on top of that, it was also dropping Cobalt Strike, which is another fun tool that we see used in every single incident lately. It feels like, um, which means that this can give attacker full control of a compromised device.

Natalia Godyla: So, what are we doing to help protect customers against IcedID? In the blog you stated that we are partnering with a couple of organizations, as well as working with Google.

Emily Hacker: Yes. So we have notified Google of this activity because it is obviously abusing some of their infrastructure in terms of the sites at And they seem to be doing a pretty good job in terms of finding these and taking them down pretty quickly. A lot of times that I'll see new emails come in, I'll go to, you know, click on the link and see what it's doing. And the site will already be taken down, which is good. However, the thing about security is that a lot of times we were playing Catch Up or like, Whack-A-Mole, where they're always just gonna be a step ahead of us because we can't pre block everything that they're going to do. So this is still, um, something that we're also trying to keep an eye on from, from the delivery side as well.

Emily Hacker: Um, one thing to note is that since these are coming from legitimate emails that are expected is that I have seen a fair bit like, uh, a few of these, uh, actually, um, where the, the customers have their environment configured in a way where even if we mark it as phish, it still ends up delivered. So they have a, what is like a mail flow rule that might be like allow anything from our contact form, which makes sense, because they wouldn't wanna be blocking legitimate requests from co- from customers in their contact form. So with that in mind, we also wanna be looking at this from the endpoint. And so we have also written a few rules to identify the behaviors associated with the particular IcedID campaign.

Emily Hacker: And it will notify users if the, the behaviors are seen on their machine, just in case, you know, they have a mail flow rule that has allowed the email through, or just in case the attackers change their tactics in the email, and it didn't hit on our rule anymore or something, and a couple slipped through. Then we would still identify this on the endpoint and not to mention those behaviors that the rules are hitting on are before the actual IcedID payload is delivered. So if everything went wrong in the email got delivered and Google hadn't taken the site down yet, and the behavioral rule missed, then the payload itself is detected as I study by our antivirus. So there's a lot in the way of protections going in place for this campaign.

Nic Fillingham: Emily, I, I wanna be sort of pretty clear here with, with folks listening to the podcast. So, you know, you've, you've mentioned the, the a, a couple of times, and really, you're not, you're not saying that Google has been compromised or the infrastructure is compromised simply that these attackers have, uh, have come up with a, a, you know, pretty potentially clever way of evading some of the detections that Google, uh, undoubtedly runs to abuse their, their hosting services, but they could just evasively has been targeting OneDrive or-

Emily Hacker: Mh-mm-hmm (affirmative).

Nic Fillingham: ... some other cloud storage.

Emily Hacker: That's correct. And we do see, you know, attackers abusing our own infrastructure. We've seen them abusing OneDrive, we've seen them abusing SharePoint. And at Microsoft, we have teams, including my team devoted to finding when that's occurring and remediating it. And I'm sure that Google does too. And like I said, they're doing a pretty done a good job of it. By the time I get to a lot of these sites, they're already down. But as I mentioned, security is, is a game of Whack-A-Mole. And so for, from Google point of view, I don't envy the position they're in because I've seen, like I mentioned hundreds upon hundreds of these emails and each one is a using a unique link. So they can't just outright block this from occurring because the attacker will just go and create another one.

Natalia Godyla: So I have a question that's related to our earlier discussion. You, you mentioned that they're evading the CAPTCHA. I thought that the CAPTCHA was one of the mechanisms in place to reduce spam.

Emily Hacker: Mh-mm-hmm (affirmative).

Natalia Godyla: So how is it doing that? Does this also indicate that we're coming to a point where we need to have to evolve the mechanisms on the forms to be a little bit more sophisticated than CAPTCHA?

Emily Hacker: I'm not entirely sure how the attackers are doing this because I don't know what automation they're using. So I can't see from their end, how they're evading the CAPTCHA. I can just see that some of the websites that I know that they have abused have a CAPTCHA in place. I'm not entirely sure.

Nic Fillingham: Emily is that possible do you think that one of the reasons why CAPTCHA is being invaded. And we talked earlier about how the, sort of the grammar of these mails is actually quite sophisticated. Is it possible? This is, this is a hands on keyboard manual attack? That there's actually not a lot of automation or maybe any automation. And so this is actually humans or a human going through, and they're evading CAPTCHA because they're actually humans and not an automated script?

Emily Hacker: There was another blog that was released about a similar campaign that was using the abusing of the contact forms and actually using a very similar lore with the illustrators and the, the legal Gotcha type thing and using That was actually, it was very well written and it was released by Cisco Talos at the end of last year, um, at the end of 2020. So I focused a lot on the email side of this and what the emails themselves looked like and how we could stop these emails from happening. And then also what was happening upon clicks over that, like I said, we could see what was happening on the endpoint and get these to stop.

Emily Hacker: This blog actually focused a lot more on the technical aspect of what was being delivered, but also how it was being delivered. And one thing that they noted here was that they were able to see that the submissions were performed in an automated mechanism. So Cisco Talos was able to see that these are indeed automated. I suspected that they were automated based on the sheer volume, but I Talos is very good. They're very good intelligence organization. And I felt confident upon reading their blog that this was indeed automated, how it's being captured though, I still don't know.

Natalia Godyla: What's next for your research on IcedID? Does this round out your team's efforts in understanding this particular threat, or are, are you now continuing to review the emails, understand more of the attack?

Emily Hacker: So this is certainly not the end for IcedID. Through their Microsoft Security Intelligence, Twitter account. I put out my team and I put out a tweet just a couple of weeks ago, about four different IcedID campaigns that we were seeing all at the same time. I do believe this was one of them. They don't even seem related. There was one that was emails that contained, um, zip files. There was one that contained emails that contained password protected zip files that was targeting specifically Italian companies. There was this one, and then there was one that was, um, pretending to be Zoom actually. And that was even a couple of weeks ago. So there's gonna be more since then. So it's something that, like I mentioned briefly earlier, IcedID almost feels to be kind of, it feels a little bit like people are calling it like a, the next wave of replacement after Emotech are taken down.

Emily Hacker: And I don't know necessarily that that's true. I don't know that this will be the new Emotech so to speak, Emotech was Emotech And IcedID is IcedID but it does certainly feel like I've been seeing it a lot more lately. A lot of different attackers seem to be using it and therefore it's being delivered in different ways. So I think that it's gonna be one that my team is tracking for awhile, just by nature of different attackers using it, different delivery mechanisms. And it'll be, it'll be fun to see where this goes.

Nic Fillingham: What is it about this campaign or about this particular technique that makes it your Moby Dick-

Emily Hacker: (laughs)

Nic Fillingham: ... if I may use the analogy.

Emily Hacker: I don't know. I've been thinking about that. And I think it has to do with the fact that it is so, like, it just feels like a low blow. I don't know. I think that's literally it like they're abusing the company's infrastructure. They're sending it to like people whose job is to make sure that their companies are okay. They're sending a fake legal threat. They're using legit Google sites. They're using a legit Google authentication, and then they're downloading IcedID. Like, can you at least have the decency, descend to crappy like unprotected zip attachment so that-

Nic Fillingham: (laughs)

Emily Hacker: ... we at least know you're malicious, like, come on. It's just for some reason it, I don't know if it's just 'cause it's different or if it's because I'm thinking back to like my day before security. And I, if I saw this email as this one that I would fall for, like maybe. And so I think that there's just something about that and about the, the fact that it's making it harder to, to fully scope and to really block, because we don't want to block legitimate contact emails from being delivered to these companies. And obviously they don't want that either. So I think that's it.

Nic Fillingham: What is your guidance to customers? You know, I'm a security person working at my company and I wanna go run this query. If I run this, I feel like I'm gonna get a ton of results. What do I do from there?

Emily Hacker: That's a good question. So this is an advanced hunting query, which can be used in the Microsoft Security portal. And it's written in advanced hunting query language. So if a customer has access to that portal, they can just copy and paste and search, but you're right. It is written fairly generically to a point where if you don't have, you know, advanced hunting, you can still read this and search and whatever methodology, whatever, you know, searching capabilities you do have, you would just have to probably rewrite it. But what this one is doing the top one, 'cause I, I have two of them written here. The first one is looking specifically at the email itself. So that rejects that's written there is the, um,

Emily Hacker: All of the emails that we have seen associated with this have matched on that rejects. There was this morning, like I said, I was talking to a different team that was also looking into this and I'm trying to identify if she found, um, a third pattern, if she did, I will update the, um, AHQ and we have, we can post AHQ publicly on the Microsoft advanced hunting query, get hub repo, which means that customers can find them if we, if we change them later and I'll be doing that if that's the case, but point being this rejects, basically it takes the very long, full URL of this and matches on the parts that are fairly specific to this email.

Emily Hacker: So they all contain, you know, some of them contain ID, some of them don't, but they all contain that like nine characters, they all contain view. It's just certain parts of the URL that we're seeing consistently. And that's definitely not by itself going to bubble up just the right emails, which is why have it joined on the email events there. And from there, the, I have instructed the users to replace the following query with the subject line generated by their own contacts, their own websites contact submission form. What I have in there are just a few sample subject lines. So if your website contact form generates the subject line of contact us or new submission or contact form, then those will work. But if the website con-, you know, contact form, I've seen a bunch of different subject lines. Then what this does is that it'll join the two. So that it's only gonna bubble up emails that have that with that specific pattern and a subject line relating to the contact form.

Emily Hacker: And given the searching that I've done, that should really narrow it down. I don't think there's going to be a ton in the way of other contact emails that are using that are showing up for these people. I wouldn't be surprised if this did return one email and it turned out to be a malicious email related to this campaign. But if the contact form generates its own subject line per what the user inputs on the website, then, you know, the screenshots that are in the blog may help with that, but it might be more difficult to find in that case. There's a second advanced hunting query there, which we'll find on the endpoint.

Natalia Godyla: And I know we're just about at time here, but one quick question on endpoint security. So if a customer is using Microsoft Defender for endpoint, will it identify and stop IcedID?

Emily Hacker: Yes, it will. The IcedID payload in this case, we're seeing Defender detecting it and blocking it. And that was what, one of the things I was talking about earlier is that Defender is actually doing such a good job. That it's a little bit difficult for me to see what's, uh, gonna happen next because I'm limited to, um, seeing kind of what is happening on customer boxes. And so, because our products are doing such a good job of blocking this, it means that I don't have a great view of what the attacker was going to do next because they can't, 'cause we're blocking it. So it's of mostly a win, but it's stopping me from seeing if they are planning on doing, you know, ransomware or whatever, but I'd rather not know if it means that our customers are protected from this.

Nic Fillingham: Well, Emily Hacker, thank you so much for your time. Thanks to you and Justin for, for working on this. Um, we'd love to have you back again on Security Unlocked to learn more about some of the great work you're doing.

Emily Hacker: Definitely, thank you so much for having me.

Natalia Godyla: Well, we had a great time unlocking insights into security, from research to artificial intelligence. Keep an eye out for our next episode.

Nic Fillingham: And don't forget to tweet us @msftsecurity or email us at, with topics you'd like to hear on a future episode. Until then, stay safe.

Natalia Godyla: Stay secure.