Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ef35af582243ff4…

MALICIOUS

PDF

75.8 KB Created: 2021-03-08 13:55:32 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 942565f4312a9256441f15024f5959ef SHA-1: 219d7f90f7d3ffc612fc33a991ccc74ea6215543 SHA-256: 8ef35af582243ff47b394449c22af39c12b0866aadb6b793d9297b6f06d0e89b
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://crophysi.ru/award?keyword=atramentowe+serce+pdf+chomikuj PDF link annotation
    • http://vorecan.space/75757642810dcvjm.pdfIn PDF document text
    • https://nupigefaxobabu.weebly.com/uploads/1/3/1/0/131070289/8973462.pdfIn PDF document text
    • https://sitoluvumoroge.weebly.com/uploads/1/3/4/7/134762666/3510196.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379610/normal_6036ca084effc.pdfIn PDF document text
    • https://bobujiwa.weebly.com/uploads/1/3/1/0/131070874/8df708d9b6.pdfIn PDF document text
    • https://rugomekedakore.weebly.com/uploads/1/3/5/3/135302214/9728b3d9a1109e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4472768/normal_5fd85b6690be2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411229/normal_5fd9d27162855.pdfIn PDF document text
    • http://maxist.ru/bottle_biology_booksx7av.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4487625/normal_6028923338336.pdfIn PDF document text
    • https://xexajuxeleseg.weebly.com/uploads/1/3/4/5/134592224/neneravolorozi-zopenejusawomep-wuwogobukedajib-zokiz.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/saziwijaxodav/dungeons_and_dragons_3._5e_character_sheet.pdfIn PDF document text
    • https://3e80c8bf-0031-4ca1-bfa9-4484641fefed.filesusr.com/ugd/08103e_d3e54c15d6cb48b3a557f0e9cf91f47c.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/50c1f9e6-7081-41af-b43d-815390dd8e57/la_divina_comedia_de_dante_alighieri_genero_literario.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5de93c3a-0cf4-4d3e-9e0d-ebc87564e238/1233966968.pdfIn PDF document text
    • https://df6a9abb-74f3-47e1-b359-fe6d1019da36.filesusr.com/ugd/7921d2_0c55f64bf3294517bf73cdcb36625be9.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/1a3cd8a1-0ffd-49d8-a37c-3a7d7ccb4ae3/wixedofogabewaronojoxuw.pdfIn PDF document text
    • https://s3.amazonaws.com/jepavilutabilel/tanorapuxivodubidudo.pdfIn PDF document text
    • https://d71fc03c-aea6-48f7-a990-8afffb22108d.filesusr.com/ugd/3de8a6_4615de732117410c85d6db22ebd2be49.pdf?index=trueIn 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_off0000ea3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA3A 5584 bytes
SHA-256: e201dcd15e352955b82ed31bc8f1d85b672e5124a02f39f6027dd473dddc333f
font_01_sfnt_off0000fd27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD27 11004 bytes
SHA-256: d50ab4eaef7f42167121d383391057b54a25c7987e641f8d62cbdc16bb50c47f