Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ba63cba37236857…

MALICIOUS

PDF

80.4 KB Created: 2021-09-08 13:00:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 885ec88a99705078eed2e5e280fd76d9 SHA-1: 98417b564af0c71e3cd55aa36ef2589c41e775fb SHA-256: 4ba63cba37236857d9d5dda1a6fd3f1109674926764e9fba29ef801f64e9979e
124 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file is identified as malicious by ClamAV and exhibits characteristics of a link farm, with numerous embedded URLs pointing to potentially compromised websites or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using small PDFs as link farms on disposable hosting, suggesting an attempt to obscure the final destination or spread malicious content. The presence of multiple external URIs and the 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristic further support the conclusion that this document is designed to redirect users to malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.4058

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://philabc.ru/uplcv?utm_term=xiaomi+bluetooth+receiver+english+manual PDF link annotation
    • http://montaze.org/democms/userfiles/file/vimarirupa.pdfIn PDF document text
    • http://tongchangkj.com/uploadfile/file///2021090722435122.pdfIn PDF document text
    • https://afma.pt/site/upload/file/mazokeditubomapewutatub.pdfIn PDF document text
    • https://accidentmatters.com/ckfinder/userfiles/files/35440448871.pdfIn PDF document text
    • http://helenhotel.vn/upload/files/xomajosojatosajebitoxi.pdfIn PDF document text
    • https://e-uchebnici.com/img/file/20248954339.pdfIn PDF document text
    • https://alcoquimicos.com/ckfinder/userfiles/files/92828212189.pdfIn PDF document text
    • https://m-astar.com/UserFiles/files/texufusapuwa.pdfIn PDF document text
    • http://sangtaoad.com/uploads/userfiles/file/voxaximapuxipige.pdfIn PDF document text
    • http://stacjaregeneracja.pl/userfiles/file/wekegoxozakiputajifexuru.pdfIn PDF document text
    • http://lamachine.nl/userfiles/file/42894847867.pdfIn PDF document text
    • http://nfc-lampang.com/user_img/files/63367421948.pdfIn PDF document text
    • https://cbconsulting112.ca/userfiles/files/7328755280.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/c42f69b8fe2f7fb2c9121f4979af6f66/wamijupikiwuzetepiratas.pdfIn PDF document text
    • https://www.tunnel.de/files/uploaded/file/gediwadisitoranuzenu.pdfIn PDF document text
    • https://susta.vn/userfiles/file/49707273023.pdfIn PDF document text
    • https://beauti-full.ru/uploads/files/92308131811.pdfIn PDF document text
    • http://www.boldino-hotel.com/ckfinder/userfiles/files/56471815876.pdfIn PDF document text
    • http://daeryuhealthcare.com/ckupload/files/bijelevixejoliseluf.pdfIn PDF document text
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/16137dbb9e3643---97019703286.pdfIn PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/6cbc66a18790060e190a78c122675dd2/75049530037.pdfIn PDF document text
    • https://soosekszer.hu/upload/files/gidurelagilijibut.pdfIn PDF document text
    • http://graylegalservices.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gitojeziwu.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ea24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA24 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001023b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1023B 10988 bytes
SHA-256: a0607ebd14c8280388ae3f166c9c9e55043ab9c000036b0f87f4cd5f9600c1e3