Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d1751a9c6c63246…

MALICIOUS

PDF

79.5 KB Created: 2021-08-14 06:52:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: fd9b2e4040cd04d919fd82c5020bcb65 SHA-1: 6dffeff2d3e029e4607d3f2573ec169e552183e3 SHA-256: 8d1751a9c6c63246b57a4b31ab95a356bc4b2158a701e9c9c3bd8bf3e296069a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection. It functions as a link farm, directing users to numerous potentially compromised or disposable hosting sites. The presence of external URIs and link farm indicators suggests an attempt to distribute malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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 http://ubestsports.com/imager/files/20210616184735.pdf In PDF document text
    • https://ntc-container.com/upload/files/30184592037.pdfIn PDF document text
    • http://nuovartea.eu/userfiles/files/xosufofimo.pdfIn PDF document text
    • http://tramtronbetong.com/uploads/userfiles/file/46782843181.pdfIn PDF document text
    • http://bhhangkhong.com/upload/images/files/wogonipidowopameboboxuxa.pdfIn PDF document text
    • http://hongdacable.com/d/files/makun.pdfIn PDF document text
    • http://hoanggiaphatland.com/uploads/image/files/zigagazejosinomitut.pdfIn PDF document text
    • http://fotossc.pl/_files/file/89102440764.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/5749ba89c3c619e7250cc12fcfaa121d/vedivola.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c1ef16950c---goras.pdfIn PDF document text
    • http://maxtarget.by/ckfinder/userfiles/files/16553973235.pdfIn PDF document text
    • http://ankamet.com/userfiles/file/bibexonetek.pdfIn PDF document text
    • http://cosmickino.ru/sadm_files/71068069432.pdfIn PDF document text
    • http://biomassasia.net/data_ed/userfiles/file/mijubotosafilowevowe.pdfIn PDF document text
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/bfqch96jogbvd92v3ihpu9esb7/51466034946.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160eff80da7800---venukegelipebo.pdfIn PDF document text
    • https://www.luthier-auxerre.fr/ckfinder/userfiles/files/letutizoparafifisig.pdfIn PDF document text
    • https://ranagro.com/files/10578646135.pdfIn PDF document text
    • http://amindoost.ir/images/upload/files/kabazitevukokonosu.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/16075e1538bdb4---baxarolovug.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/90vf9f8nd38r396aeatqi703n1/judoxakelekadipufezetejir.pdfIn PDF document text
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/ae3a78830611fc8af0d5c2010525aa4c/66907487940.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=hippopotamus+for+christmas+lyricsPDF 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_off0000d433.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD433 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ec4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC4A 10712 bytes
SHA-256: 084f2ecff8120b4391eeba036ac40613d0fdfbc78bc4ba6ad715358728791970
font_02_sfnt_off000104e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104E9 16312 bytes
SHA-256: e59fc25bc9d7a82692e77ee57236bc57a0fb1f12bb2d416e490baefb8989410a