Malicious PDF — malware analysis report

Static analysis result for SHA-256 83cae662ec1c63dd…

MALICIOUS

PDF

80.1 KB Created: 2021-06-24 09:35:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 7ffa054b717662192751a391b21a6e7e SHA-1: a83d1e0e3d70d7dc5cc72eceb74da551e9ee3a39 SHA-256: 83cae662ec1c63ddd6953666b874fdba7b0c5a5f72a5e033d78e1e077c3e8690
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains multiple embedded URLs, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate a phishing or trojan payload. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a malicious document designed to trick users into downloading further malware or visiting phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://irlanc.ru/uplcv?utm_term=safe+rte+exam+questions+and+answers PDF link annotation
    • http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af8d24223c2---28305281200.pdfIn PDF document text
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/89dk12n0k1s8rvk67jtlak3bnq/97537585069.pdfIn PDF document text
    • http://hphs1958reunion.com/clients/47465/File/genujusigeladilem.pdfIn PDF document text
    • http://high-keenltd.com/userfiles/file/58777676576.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb24f8c175---kegalefexajoxiwofi.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607fe2c1913d5---titadejegazalavugu.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160966d1eed779---motisow.pdfIn PDF document text
    • https://aquatrustfina.com/userfiles/file/93662729676.pdfIn PDF document text
    • https://montpellier-business-plan.com/mbp/upload/images/images/upload/ckfinder/24539991769.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/f1f4ac61b7f23658907c8427d401e72d/92827962346.pdfIn PDF document text
    • http://championshipsportsrings.com/clients/23492/File/65897723299.pdfIn PDF document text
    • http://spreewaldatelier.de/img/editor/file/fukejoxiwebef.pdfIn PDF document text
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077e305baa6c---15082385334.pdfIn PDF document text
    • http://deltastal.ru/userfiles/file/fubidiv.pdfIn PDF document text
    • https://remoteworkerclub.com/wp-content/plugins/super-forms/uploads/php/files/ef2ef9337a151bb4a9916806d21c5548/34396588027.pdfIn PDF document text
    • https://atcotourismtravel.com/userfiles/file/punilume.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f60e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF60E 5408 bytes
SHA-256: 223caefe227d849e097b0c78c27a6980be9c6c73707ced4206c916cb28d1babe
font_01_sfnt_off00010871.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10871 12012 bytes
SHA-256: 5f4b54edfb2150b754e92d5110d08a102d485eb06b479e3d18d9943035d54cd4