ASEC Weekly Phishing Email Threat Trends (April 2nd, 2023 – April 8th, 2023)

AhnLab Security Emergency response Center (ASEC) monitors phishing email threats with the ASEC automatic sample analysis system (RAPIT) and honeypot. This post will cover the cases of distribution of phishing emails during the week from April 2nd, 2023 to April 8th, 2023 and provide statistical information on each type. Generally, phishing is cited as an attack that leaks users’ login account credentials by disguising as or impersonating an institute, company, or individual through social engineering methods. On a broader note, the act is a technical subterfuge that enables the threat actor to perform attacks such as information leaks, malware distribution, and fraud against various targets. The focus of this post will be on the fact that phishing attacks mainly occur through emails. We will also provide a detailed classification of various attack methods that are based on phishing emails. Furthermore, we will make an effort to minimize user damage by introducing new attack types that have never been found before and emails that require users’ caution, along with their keywords. The phishing emails covered in this post will only be those that have attachments. Emails that have malicious links in the body without attachments will be excluded.

Phishing Emails

During this week, the most prevalent threat type seen in phishing email attachments was FakePage with 47%. FakePages are web pages where the threat actor has imitated the screen layout, logo, and font of the real login pages or advertising pages, leading users to enter their account and password information. The input information is sent to the threat actor’s C2 server or used to induce users to access other fake websites. See <FakePage C2> below The second most prevalent threat type was Downloader (18%), which includes loaders such as SmokeLoader and GuLoader. It was then followed by Worm (15%) and Infostealers (10%) like AgentTesla and FormBook that leak user credentials saved in web browsers, emails, and FTP clients. Aside from those mentioned above, Trojan (5%) and Dropper (5%) types were detected. The threat types using phishing email attachments and their order of prevalence are similar to the order of malware distribution published weekly in the <ASEC Weekly Malware Statistics>.

File Extensions in Phishing Emails

We have identified which file extensions were used by the threats above for the distribution of email attachments. FakePages were distributed through web pages script (HTM, HTML, SHTML) documents that must be executed with a web browser. Other malware, including Infostealer and downloader, came attached to emails with file extensions including compressed files (ZIP, 7Z, GZ, etc.).

Cases of Distribution

The following are distribution cases that occurred during the week from April 2nd, 2023 to April 8th, 2023. The cases will be classified into FakePage and malware types, including Infostealer, Downloader, Exploit, and Backdoor. The numbers in email subjects and attachment filenames are unique IDs and may vary depending on the email recipient. Distribution cases with Korean subjects were also found. These are cases that specifically targeted Korean users instead of propagating themselves globally using identical English subject and texts.

Case: FakePage

Email SubjectAttachment
RE: [****] ** number 1 & 2 EDM consultation related APCFS poster announcement materialNM.pdf
Access to your email will be restricted confirmation failedfi***ce@********* Update-2023.htm
RE: **** number 7 & 8 DeNOx facilities request for performance improvement estimateMI.pdf
Re: [****] FGD pipe rack *** company plumbing Inform. request for forwarding and applicationIR.pdf
FWD: [DHL] Notice on Import Tax Payment Deadline – (INV and AWB)Original Shipping Doc#GM53726192.pdf.htm
Na*** Cou**** uploading all keywordsKTX.pdf
FW: purchase order attachedPO20230403.html
[External]FW: [******] Request to review affiliate service customer eventRA.pdf
User email disconnected from service********.****@********* Update-2023.htm
FW: January 2019 Security Day content sharingUT.pdf
[External]FW: [**] Request to issue certificate of career and disciplinary action form (***)EN.pdf
RE: RE: RE: RE: ****) ** number 1 & 2 EDM consultation related surface SEM measurement photoCT.pdf
SRPI Project quotation requestSpecfication for SRPI Project.htm
Quotation QUO91019Quote.html
New DHL Shipment Document Arrival Notice / Shipping Documents / Original BL, Invoice & Packing List(DHL) Original BL, PL, CI Copies.htm
FedEx Shipment 811470484778: Parcel Scheduled For DeliveryShipping Document.html
R: New offer requestscan001.htm
A Recent Charge on your Card was UnsuccessfulAccount_Security _Message.htm
New DHL Shipment Document Arrival Notice: Shipping Documents, Original BL, Invoice & Packing List.Tracking.html
ACH Payment sent On: Monday, April 3, 2023 12:51 p.m.Swift_Payment_Confirmation.pdf.shtml
Financial Statement /acc****ing@a*********.co.krFinancial Statement.shtml
【132nd Canton Fair】b****gu@*****.**.kr.htm
New OrderPO54324567.htm
***@********* sent you files via WeTransferWeTransfer files_*****ne@*********
Re: ******.park You Have 1 New Shared DocumentTruefriend_PAYMENT_CONTRACT.pdf
ACH Payment sent On:Thursday, April 6, 2023 1:43:27 PMh***m@*********.com Voutcher.shtml
RE: IBK SWIFT PAYMENT COPYIBKPaymentSwiftApproval.html
Purchase Order PO-3242 from VP Group Limited for sjleePO-3242.html
ACH Payment sent On:Thursday, April 6, 2023 3:20:47 PMs***m@*********.com Voutcher.shtml
Re:Re:Re: Quotation orderNew_Order Inquiry.Htm
Re : invoice for MARCH 2023REVISED INVOICE.shtml
Payment Transaction Notification : Successoptical PAYMENT ADVICE-US$ 168,573.htm
Your grant donation – {Mrs Jacquelline Fuller}Donation Application.docx

Case: Malware (Infostealer, Downloader, etc.)

Email SubjectAttachment
Open outstanding account statementOpen account statement.PDF.jar
AttachmentNEW ENQUIRY-pdf.gz
Re: Re: Return invoice for PaymentReturn invoice.rar
[DHL] Acceptance of Import Declaration (Payment Before Acceptance) – 7759303436[DHL] 7759303436.rar
Your Shipment has Arrived Tracking Number!Protected Copy Doc 099876858.rar
PO#40823-LiDe Industry Group Co LimitedPO#40823.rar
Request for quotation – lpr no. 8661RDA 8661 SEBASTIANO.rar
NEW ORDER PO # IF23029361209PO # IF23029361209.rar
RE: COSTCO Purchase Order #180222/CT24 & #160222/CT71COSTCO Purchase Order.rar
PURCHASE ORDER 163403Drawings.gz
Re: Fw: Payment for Outstanding InvoiceINV19384783.html
World Surfaris Remittancebalance$600,000.65-pdf.gz
Product EnquirySKM51092BY210.IMG
PO NO. 42236592PO#NO42236592000010.pdf.ARJ
Request from Octopus Asia PacificSKMB710925U10.xz
SumiP Machine equipment InquirySUMIP MACHINE EQUIPMENT INQURIY.rar
Re[3]: super smart pics privatebest_img.jpg.scr
Order ListOrder-List.iso
Re: Document PO4377J7PDocument 54737.7z
Fwd: Re: Advanced Payment ConfirmationAdvanced Payment – Ref_001299384596OBR11522.gz
KCI – Statement of Account – 30th march 2023statement for HADCO S.A.O.C.exe
Purchase Order PO GEC/PO/18667 for EHAF – KSA supply ProjectPDF1567256210241910840.r01
Deposit made to your accountDeposit slip.exe
FW:New PO#SPL036570 + RFQ036647New PO#SPL036570.pdf.GZ
Technical DatasheetTechnical_ Datasheet.7z
Re: Price Qoutation RequestRFQ 2008817838749.PDF.Z
Request for QuoteRequest for Quote.PDF.7z
Payment Advice – Ref: [HSBC41057723] / RFQ Priority PaymentPayment Advice – Ref HSBC41057723 PDF.7Z
RE: Surat Pesanan – RFQPT.GLOBAL.PDF.rar
Payment receipt statusPayment_swift 20289820.pdf.gz
DHL AWB – Invoice & Shipping DocumentsDHL AWB – Invoice & Shipping Documents.gz
sales contract-876 & New-OrderExecutiveship PO 06042023.arj
Re:Top Urgent ORDERNew Order-3790028747.img
Re[5]: super wonderful images PRIVATEbest-phot.gif.scr
beautiful picturessuperimg.gif.scr
Re[5]: very cool picswildpic.gif.pif
Re[4]: super nice images don’t showgreat_imgs.gif.exe
very wonderful photos only for youprivate-pctrs.jpg.scr
Re[2]: very cool picsgreataction.gif.exe
sexy photos PRIVATEprivatepic.jpg.scr
super sexy pics PRIVATEmy-act.jpg.scr
Re[5]: very nice pictures very importantbest_images.jpg.scr
Re[3]: smart photo FOR YOU ONLYprv-pic.scr
super beautiful photo PRIVATEmy-images.jpg.pif
nice photos privatesexpctrs.pif
very nice photosex__phot.jpg.pif
nice picsprivatephot.gif.exe
Re[2]: nice picture imortantgreat_images.exe
smart picturessexscene.exe
Re: super cool picsgreat_act.jpg.pif
very cool picture PRIVATEthe_phot.gif.scr
wonderful photomypctrs.jpg.pif
sexy imagessexpic.jpg.pif
Re[3]: beautiful photo just for youbest__pctrs.gif.pif
very cool pics don’t showthe-plp.gif.exe
Re[2]: smart picturesprivphotos.jpg.scr
Re: smart picsprvimgs.jpg.scr
sexy picsmyscene.pif
smart imagessexscene.scr
Re: very cool photos FOR YOU ONLYgreat-img.scr
sexy pictures privatesexpctrs.exe
Re: cool picture imortantprv__img.gif.scr
Re[4]: sexy imagesprivaction.exe
Re[2]: super smart picturesfuckpctrs.jpg.scr
Re: super nice images only for yougreat-pic.pif
Re: very nice photofuckphotos.gif.exe
beautiful pictures very importantsexaction.exe

The ASEC analysis team has selected keywords that users must look out for, based on the distribution cases above. If these keywords are included in the subject of the email, or if the same characteristics are found, users must exercise strict caution as they may be phishing emails from threat actors. 

Keywords to Beware of: ‘PDF’   

The keyword for this week is ‘PDF.’ For this week, the phishing emails attached with PDF files had titles including power plant equipment and were disguised as event promotional materials for certain companies. Instead of average documents such as invoices and purchase orders, the emails were disguised as being related to some power stations and equipment. As for the attached PDF files, their names and content were very similar despite the difference in the distributed emails’ names. The attachment names were a combination of two alphabets. When the file is viewed, it impersonates Microsoft Azure and prompts users to open it. When users click the open button, a page for entering the ID and password appears. Attempting to log in will result in account credentials being leaked to the attacker’s phishing server, as well as the user PC being infected with downloaded Qakbot malware. You can check for more details on this ASEC blog post (

  • Phishing URL: https[:]//[.]zw/ei/ei.php

FakePage C2 URL

When users enter their IDs and passwords on the login pages among the FakePages created by the threat actor, their information is sent to the attacker’s server. The list below shows the threat actor’s C2 addresses of fake login pages distributed during the week.

  • http[:]//demo[.]double-eleven[.]hk/wordpress/wp-content/plugins/6f7ecdf697634e1181a754ea4ca0913f/y/mm/mmd/index/fedex/FedExpress[.]php
  • https[:]//newtrp[.]com/gbooonus/processor[.]php
  • https[:]//formspree[.]io/f/myyazkbv
  • https[:]//cranecenter[.]ru/Xx/cloudlog[.]php
  • https[:]//www[.]btdpipe1ine[.]com/oc/fdpxoGur23f[.]php
  • http[:]//www[.]znbs[.]co[.]zm/Uploads/Document/DHL/log[.]php
  • https[:]//formbold[.]com/s/91wBz
  • https[:]//chuyenphat[.]nascoexpress[.]com/wp-includes/noshaking/peeking[.]php
  • https[:]//instelator-center[.]co[.]il/isso[.]checkerz[.]php
  • http[:]//chikashikakehi[.]sakura[.]ne[.]jp/file/slot-gacor-maxwin/welcome[.]php
  • http[:]//mail[.]alicevik[.]com[.]tr//makechina/lognet1[.]php
  • https[:]//kazan-oil[.]ru/fidders/msms/vmxll[.]php
  • https[:]//jaslyimpex[.]com/catalog/44/A/Excel[.]php
  • https[:]//www[.]palazzocalo[.]com/cxHiEtx/Exc/Excell[.]php

Attacks using phishing emails are disguised with content that can easily deceive users, such as invoices and tax payments, to induce users to access fake login pages or execute malware. Fake login pages are evolving by the second to closely resemble the original pages. The attackers pack malware in compressed file formats to escape the attachment scans of users’ security products. Users must practice strict caution and refer to recent cases of distribution to avoid being exposed to infection by malicious phishing emails. The ASEC analysis team recommends users follow the email security guidelines below.

  • Do not execute links and attachments in emails from unverified senders until they are proven to be credible.
  • Do not enter sensitive information such as login account credentials until the site is found to be reliable.
  • Do not execute attachments with unfamiliar file extensions until they are found to be reliable.
  • Use security products such as antimalware software.

According to the MITRE ATT&CK framework, phishing email attacks correspond to the following techniques.

  • Phishing for Information (Reconnaissance, ID: T1598[1])
  • Phishing (Initial Access, ID: TI1566[2])
  • Internal Spearphishing (Lateral Movement, ID: T1534[3])

Subscribe to AhnLab’s next-generation threat intelligence platform ‘AhnLab TIP’ to check related IOC and detailed analysis information.


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