The ASEC analysis team 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 January 8th, 2023 to January 14th, 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 Infostealer, taking up 38%. Infostealer includes malware such as AgentTesla and FormBook, and they leak user credentials saved in web browsers, emails, and FTP clients. It was then followed by FakePage, which took up 34%. 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 third-in-line was Exploit type with 12%. A majority of them were document files with the formula editor (EQNEDT32.EXE) vulnerability. Aside from these, Downloader (8%), Worm (7%), and Trojan (1%) 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. Among the phishing email attachment types this week, the distribution of ONE extension files (3%) is notable. OneNote is a digital note-taking app developed by Microsoft, which unlike word processing software, allows users to insert content anywhere within the pages. FakePages were distributed with PDF documents or web pages scripts (HTML, SHTML, HTM) that must be executed with a web browser. Other malware, including Infostealer and downloader, came attached to emails with various file extensions including compressed files (ZIP, RAR, GZ, etc.), IMG disk image files, XLS, and ONE document files. With the exception of FakePages that are distributed through web pages script files and PDFs, other malware types were distributed with a variety of file extensions regardless of the threat type.
Cases of Distribution
The following are distribution cases that occurred during the week from January 8th, 2023 to January 14th, 2023. The cases will be classified into fake login pages 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 the identical English subject and text.
Case: FakePage
| Email Subject | Attachment |
| Confirmed Order ref. 23979 | MX-3114N_20220908_011044 (1).htm |
| Incoming Shipment Notification for ******@********.com | AWB#93230 .html |
| Deposit – P/I SYW220 / Re: 2.5gPP | Deposit USD9,009.00 PI SYW220.pdf.htm |
| Deposit – P/I SYW220 / Re: 2.5gPP | SWT-#AG027392KL282.jpg.htm |
| [DHL] shipping invoices for payment | invoice & Tracking NumberHT2.htm |
| [DHL] shipping invoices for payment | payment_doc & shipment#7221HKT.shtml |
| Re: Please Find Attached | Document.htm |
| Fw: Statement(SOA) | Statement.pdf |
| FW: Quotation – RFQ request: From Win-Win Trade Co.,Ltd | New_Order.Pdf.htm |
| FedEx Shipment Arrival Notification | AWB#989345874598.html |
| Urgent/Fiam – order confirmation | OC0000352877.htm |
| Project for 2023 order | doc22314.shtml |
| Factura electrónica – 3990575 | f7720cf0-9645-11ed-8372-44a842253043.html |
| Your DHL Express shipment with waybill number 4608948875 is on its way. | DHL SHIPPING DOCUMENTRECIEPT.html |
| Factura electrónica – 4537675 | 1fd9fbcf-9646-11ed-b1d1-44a842253043.html |
| CENTRUM – Payment Documents for Validation | CENTRUM – Contract Documents.html |
| Fw: Statement(SOA) | Statement.pdf |
| VENDOR FORM INVIOCE. | VENDOR-INVOICES.shtml |
| RE: FW: Shipment # | Shipping-Document#0004-PDF.htm |
| AW: Purchase Order 291765 – JF KOREA Co.,Ltd For Urgent Delivery | Purchase Order JF KOREA Co Ltd JAN.html |
| Salary Upgrade Review (Final Post-Covid-19 listing) | Salary_Upgrade_ Datasheet_January_ 2023.zip |
| Artel Electronics LLC – PROPOSAL | Artel Electronics LLC – PROPOSAL .html |
| Factura Pendiente – 576599 | b7bde4ee-9657-11ed-bd71-44a842253043.html |
| Confirm your delivery address | AWB#3230922.html |
| NEW ORDER SUSFINE-YJ207.pdf | NEW ORDER SUSFINE-YJ2022.pdf.htm |
| VENDOR FORM INVIOCE. | VENDOR-INVOICES.shtml |
| FedEx Arrival Notice. | FedEx – vims7- AWB.pdf.htm |
| Segue (NFSe) N.003751166 | NFSe006457402.html |
| RE: FW: Shipment # | Shipping-Document#0004-PDF.htm |
| Zahlungsdetails | Bank receipt.pdf |
Case: Malware (Infostealer, Downloader, etc.)
| Email Subject | Attachment |
| Unpaid Invoice IQ0075440 | Invoice IQ0075440.one |
| Re: 2023 JAN ORDER BTB LC SCAN DOCUMENT COPY OF SANS TEST PACKGING [IMPORTANT] | January-Payment.rar |
| Urgent booking for Honeymoon | Passport and Id for booking details.docx |
| fw: informe de pago devuelto | pago devuelto.pdf.img |
| Invoice #0048006 DUE | Invoice-48006.one |
| Wire Transfer | payment.img |
| Wire Transfer | REF122553.img |
| Re: SOA Detail Payment for shipment invoices from Nov 11th – Jan 3rd | SOA Payment TT application details 10012023.xls |
| Re: NEW PROFORMA INVOICE ( PI#CNW202356034 ) – Possible E.T.D schedule (Est. 17 Jan) | PROFORMA INVOICE CNW202356034.xls |
| RE: Shipping PI CS/2022-23/024 Documents & Shipment advise Est. E.T.D |
SHIPPING DOC BLBNTHCM22120020 INVOICE PL 20230110.xls
|
| RE: Urgent Shipping Documents – MV. TAHO EUROPE | Shipping Documents 20230113.xls |
| NEW MID – FEBRUARY ORDER PO2202857 / Shipment delivery E.T.D FEB 15 | ADM NEW FEBRUARY ORDER PO2202857.xls |
| sending you my pix | mypic.zip |
| Request For Quotation | RFQ.rar |
| Thanks – Payment has been received. | AmericanExpress-Online-Services-Notification.zip |
| Vodafone PXT notification | PXTpicture Multimedia Message.zip |
| Transaction Receipt | Jackgreen-Energy-Transaction-Receipt.zip |
| Tax Agent Report – Delayed Tax Returns | TaxAgentReport.xls.zip |
| DHL Shipment Notification | Payment copy.gz |
| DHL Shipment Notification | doc.rar |
| sending you my pix | mypic.zip |
| TPG Internet: Equipment Order 8620430557 | I14516978.zip |
| Thanks – Your payment has been received. | Payment Details 79142586.zip |
| DHL Shipment Notification | dd.rar |
| AWB 50326756532 – Shipping Documents |
DHL AWB – COMMERCIAL INVOICE, BILL OF LADING,_ETC DOC.gz
|
| NEW ORDER | PO- 3861209534.zip |
| New enquiry | Quote # QU20094 – 13-01-2023.img |
| Re: Quotation… | Quotation_DEC-2022.rar |
| Delivery failed | message.zip |
| very nice pics only for you | my-scene.jpg.scr |
| MAIL SYSTEM ERROR – RETURNED MAIL | document.zip |
| very wonderful photos only for you | private_imgs.jpg.scr |
| Returned mail: see transcript for details | attachment.zip |
| sexy pictures | myphotos.gif.scr |
| Message could not be delivered | document.zip |
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: ‘ONE’ Extension
The keywords for this week are ‘ONE’ extension files. OneNote is a digital note-taking app developed by Microsoft, which unlike word processing software, allows users to insert content anywhere within the pages. Such ONE file was distributed in disguise as a fake invoice email. As shown in the second image, a content prompting the users to click the object is inserted to appear when users open the file via OneNote. Upon clicking the object, a malicious BAT file is downloaded and executed.
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.
- hxxps://erfgvcv.ga/abig/pdfnglw.php
- hxxps://formspree.io/f/xbjejppb
- hxxps://benti-energies.com/ftmm/Adhl.php
- hxxps://vladiolitrade.ru/lk/zender.php
- hxxps://formspree.io/f/xdovnyrz
- hxxps://iohygf.cf/content/msxl.php
- hxxps://earthsaviours.net/dh/hl.php
- hxxps://edcgfd.cf/11/msxl.php
- hxxps://proshield.ie/wp-admin/HZ/remit.php
- hxxps://barajmwtii.rest/dhl/processor1.php
- hxxps://www.niemands-land.nl/wp-admin/logsbox0/login.php
- hxxps://erfgvcv.ga/webq/msxl.php
- hxxps://iohygf.cf/content/msxl.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])
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The post ASEC Weekly Phishing Email Threat Trends (January 8th, 2023 – January 14th, 2023) appeared first on ASEC BLOG.
Article Link: ASEC Weekly Phishing Email Threat Trends (January 8th, 2023 – January 14th, 2023) - ASEC BLOG