Malicious PDF — malware analysis report

Static analysis result for SHA-256 21f9f2840cb6f29a…

MALICIOUS

PDF

104.4 KB Created: 2021-08-12 15:46:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 689eb071a65f870a99fa7dc0675f9a4b SHA-1: ce350270a0fe1ef0bd47bb652b048a8a40a84b27 SHA-256: 21f9f2840cb6f29aea145d4b524c3968d84e5634ec47e20810848c2576cbba97
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated high maliciousness. It contains numerous links, many pointing to compromised WordPress upload directories, suggesting it's designed to lead users to malicious content. The document body is unreadable, but the heuristics strongly indicate a link farm used for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bcb18de2d41---tewirojilatazeganigoki.pdf In PDF document text
    • https://tortugafilms.ca/adminfiles/file/45993928766.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ed8b6f80040---74135184120.pdfIn PDF document text
    • http://writtenmail.com/upload_images/file/89240592839.pdfIn PDF document text
    • https://fastcomputer.vn/wp-content/plugins/super-forms/uploads/php/files/928beff8aaf658a5d4a9604e27161a95/60837644039.pdfIn PDF document text
    • http://narcisse.sk/editor_uploads/files/sojewibolitomamil.pdfIn PDF document text
    • http://aitrans.org/UploadFile/file/F1202106201837484871.pdfIn PDF document text
    • https://www.herewardcarpets.co.uk/wp-content/plugins/super-forms/uploads/php/files/msnr48ki0anuv3vjhvesesccgv/81052297078.pdfIn PDF document text
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/48f22844d7fcafd711dbe651ee50e280/98377796884.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/57dbb8cc3eaf6dea6899d307889657f5/nutumozidaporebeso.pdfIn PDF document text
    • http://abwingscolley.com/uploads/files/kimetaluxub.pdfIn PDF document text
    • https://chefinhogourmet.com/wp-content/plugins/super-forms/uploads/php/files/3a131ef597dcc3572a9937d6a5aeed9f/sebolesutiganuvo.pdfIn PDF document text
    • http://diysmart.net/userfiles/file/desupewir.pdfIn PDF document text
    • http://amsasecretariat.fr/userfiles/file/mumeborilikenutonakogeba.pdfIn PDF document text
    • https://www.proctoloji.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607591edd5c67---zojevodinepurizufagi.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/16072f2947530b---lagilubavokemedesozenila.pdfIn PDF document text
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609c157373dd5---57100078927.pdfIn PDF document text
    • https://intekcanada.com/ckfinder/userfiles/files/fapumeximigedemofig.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/8af48a7906c8c761512fd953bfb249b6/kitibapusexelofakofem.pdfIn PDF document text
    • http://clear-es.net/yamituki-n/uploads/files/jatug.pdfIn PDF document text
    • http://www.egavilanes.com/ckfinder/userfiles/files/joxevigexezezug.pdfIn PDF document text
    • http://velo.hu/UserFiles//file/tebanojezumotakopal.pdfIn PDF document text
    • http://www.pics4us.de/userfiles/file/folubawojujetodizedik.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=does+magnus+chase+come+back+to+lifePDF 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_off000134a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134A7 17364 bytes
SHA-256: 7639c057ce682a80f76a9d64da70fc39c3a9d70a0da3ab50a3868976bcadd0f6
font_01_sfnt_off00016203.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16203 11016 bytes
SHA-256: 05308d0223687d0843dc96304029c29c7ef3ddeaea35d65252c63fbacb432cd3
font_02_sfnt_off00017b6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17B6E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1