Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4a5d0e45242c07c…

MALICIOUS

PDF

69.3 KB Created: 2021-09-27 22:12:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c07ef51c62f2d11def9e61e92791dff1 SHA-1: ebf871ba7cde53b82272b6e290c857796b6ee765 SHA-256: a4a5d0e45242c07ca2e6c2972d7efd4c2a4718e7550bc0d70450a5e6d16b50c9
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with several heuristics indicating it functions as a link farm, including links to compromised WordPress upload storage. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, limiting the analysis of the specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • 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
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://dom4m.de/userfiles/files/mizukipag.pdf In PDF document text
    • https://alsultantrading.ae/userfiles/files/65296635084.pdfIn PDF document text
    • https://299-45.com/CKEdit/upload/files/17192263241.pdfIn PDF document text
    • http://apsencollege.org/test/fckeditor/file/87515499177.pdfIn PDF document text
    • https://thanaclusterwestgate.leaddeehub.com/userfiles/files/ginomuvabunefofa.pdfIn PDF document text
    • https://unique-u.biz/images/uploads/file/9697598421.pdfIn PDF document text
    • http://hglobaltour.com/FileData/ckfinder/files/20210907_3B15D8F8CEA500DF.pdfIn PDF document text
    • http://chuanghuilaw.com/filespath/files/20210914132508.pdfIn PDF document text
    • http://secureyun.cn/uploadfile/file///2021091004140466.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614fec00e677a---ravos.pdfIn PDF document text
    • http://pensjonatagat.pl/userfiles/file/49613386052.pdfIn PDF document text
    • http://www.maarsehoveniers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16133edd99db6e---58116382651.pdfIn PDF document text
    • https://hobbyschuurtje-webwinkel.be/images/userfiles/file/6079352988.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/8g6b4v7q79a878cjoteakk7qrm/papuxujajirugedetime.pdfIn PDF document text
    • http://imi.vc/upload/files/68076313281.pdfIn PDF document text
    • http://tatvideo.ru/ckfinder/userfiles/files/82831635384.pdfIn PDF document text
    • http://architettomontanino.eu/userfiles/files/jakojew.pdfIn PDF document text
    • http://3dtechgroup.com/uploads/image/files/26318562586.pdfIn PDF document text
    • https://radekslodkiewicz.pl/files/file/706275221.pdfIn PDF document text
    • http://annassteen.com/ckfinder/userfiles/files/zowopatilotomalawi.pdfIn PDF document text
    • http://tupnate.com/ckfinder/userfiles/files/pisiwu.pdfIn PDF document text
    • http://www.kroonzuivel.nl/ckfinder/userfiles/files/88339192752.pdfIn PDF document text
    • https://akproauto.com/nbloom/fckuploads/file/fikujapediw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=david+guetta+ft+siaPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b168.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB168 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c97f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC97F 10324 bytes
SHA-256: 385a2b666e6d4e497e6c749f9d68ae6e2f1c3908bda6050b40d4a70346211b61
font_02_sfnt_off0000e0c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0C5 15340 bytes
SHA-256: 29796dca82d6e2294d277b08fea02107f8bb20fa78d77766b11646d2ca4dbe29