Malicious PDF — malware analysis report

Static analysis result for SHA-256 71dee8da07a03160…

MALICIOUS

PDF

72.1 KB Created: 2021-09-11 11:10:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 103ba8984583dd7daf1d72e7360af0f9 SHA-1: 22edf13d5d49092fe953e1eb3c7cf6f9f30ba528 SHA-256: 71dee8da07a0316028ce16d70394a560dfea681e985d46b903320987142e64e9
156 Risk Score

Malware Insights

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

The PDF file contains a link farm, as indicated by multiple heuristics and a large number of extracted URLs. These links point to various domains, many of which are hosted on compromised CMS platforms or disposable hosting, suggesting an attempt to distribute malicious content or conduct phishing. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9902

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://halanmilk.com/upload/files/54943760533.pdf In PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131f2ce1f714---jumobabigobimiwagewuxakuv.pdfIn PDF document text
    • http://sparkpro.lv/content/file/wipoluzulusiropedevas.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/5lrf9pccefk6u6bjaifi2k3inf/77413467214.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16138367e941c1---10796049005.pdfIn PDF document text
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/16138f85c7b200---13614125741.pdfIn PDF document text
    • https://pakistanchristiancongress.org/userfiles/file/lotomifixarijugexi.pdfIn PDF document text
    • http://dxqzx.com/ckfinder/userfiles/files/20210910_185301.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/16137899a7ca2c---12082082186.pdfIn PDF document text
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/580d96f850ff790112ef762a05f9e4c6/50131408797.pdfIn PDF document text
    • http://torby.kbo.pl/ckfinder/userfiles/files/xitenokipu.pdfIn PDF document text
    • http://dpsszczytno.pl/photo/file/fagogixubujipexo.pdfIn PDF document text
    • http://phonphangschool.com/upload/files/55061247366.pdfIn PDF document text
    • http://altaprecision.com/userfiles/file/rexofatuduloguja.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/161316d119d9d8---naxagedixuzasijoje.pdfIn PDF document text
    • http://mtsskzy.com/userfiles/file/22680369163.pdfIn PDF document text
    • https://libertyrealestate.in/ckfinder/userfiles/files/96064393698.pdfIn PDF document text
    • https://bonvoyageindia.in/ckfinder/userfiles/files/967000668.pdfIn PDF document text
    • https://www.la-providence-ehpad.fr/ckfinder/userfiles/files/50473493219.pdfIn PDF document text
    • http://jinistudy.com/_UploadFile/Images/file/50135864984.pdfIn PDF document text
    • http://www.uc-kushiro.net/images/library/File/vivetuwoduvuwomama.pdfIn PDF document text
    • http://eros-arena.de/eros/userfiles/file/ziregejikaxelilur.pdfIn PDF document text
    • http://imhkayseri.com/resimler/files/fuwubupikodenanisixum.pdfIn PDF document text
    • http://kovovyroba-nosniky.cz/UserFiles/File/20278769551.pdfIn PDF document text
    • https://przyklejki.pl/userfiles/vovobakegalutawem.pdfIn PDF document text
    • https://cambodiaangkorhomestay.com/userfiles/file/38387127234.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=how+to+unlock+sim+on+androidPDF 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_off0000bc1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC1F 15052 bytes
SHA-256: 1d91510100cac3d126b85a13c9c79ab5ec09e5e19c7fabe3b4589f5917a9fd4a
font_01_sfnt_off0000e1ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fa16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA16 10668 bytes
SHA-256: 1521711e8a970e93b269a65f9d39862bf62f26704676a31d025c755bc26e6cf4