Malicious PDF — malware analysis report

Static analysis result for SHA-256 9aee31a78eae4136…

MALICIOUS

PDF

74.0 KB Created: 2021-08-26 12:55:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 2567a75d3e75c80895befa4eaffb00e7 SHA-1: 712712c0bb1460e63f8c427c264d14cd2aa5c222 SHA-256: 9aee31a78eae4136f4c35bb76123e0edd6a3933f236003b8b469255aa8b8d4cf
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Static analysis revealed it functions as a link farm, directing users to multiple compromised websites that host further PDF files, likely as part of a phishing or malware distribution chain. The presence of numerous links on disposable hosting and compromised CMS uploads indicates a deliberate effort to obscure the true malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160b331b9b56fe---73472758540.pdf In PDF document text
    • https://blueridgelightingandcontrols.com/wp-content/plugins/super-forms/uploads/php/files/3815b4a3b5b492e4d88005b7a86148af/zonotilu.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/37151411158.pdfIn PDF document text
    • https://www.treehousecare.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607bc2a9da1e0---mexizasixupupotugonaxar.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/ni4m7b2ohj8c1pmpuasiqa8hcu/69260054913.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/160a029dfd0df2---69667567602.pdfIn PDF document text
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f2a2abd4af---22273272807.pdfIn PDF document text
    • http://prmakeup.com/Image/files/74286287523.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608379247194b---babijofebigaputisoputa.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/b05e2989bfa04a00ac5c33ea0baaf1ea/91423118528.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/bb5ac78d24e8b6fd01c2507ef8448534/gerivusegawunoz.pdfIn PDF document text
    • https://poolpoint.be/uploads/file/kebufotirolelolekezud.pdfIn PDF document text
    • https://rieker-consulting.eu/files/file/79716503724.pdfIn PDF document text
    • https://allegypttours.net/userfiles/files/xagejokazimoxinobaki.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1608502a3b410d---40002828037.pdfIn PDF document text
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/ad972f77e18c8952f19cdcb6b0286f98/97305456857.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/gci60na650hhh429op9boec0q5/jovaro.pdfIn PDF document text
    • https://www.sacict.or.th/ckfinder/userfiles/files/21136294811.pdfIn PDF document text
    • https://shieldtech.cz/ckfinder/userfiles/files/4569475215.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160c7c30f3dd65---gubazefanaruwudukipikalon.pdfIn PDF document text
    • http://piau-po21inn.com/CKEdit/upload/files/jebumojugazikojif.pdfIn PDF document text
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/225b8013f809ac456bc96ae4e9ef4b94/72277707796.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=full+charge+voltage+of+lead+acid+batteryPDF 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_off0000bedd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBEDD 16452 bytes
SHA-256: c988847052b65cad3262c891dc2e88b098b1b9a585538cc209191302e1cd4c45
font_01_sfnt_off0000e97b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE97B 10880 bytes
SHA-256: 593f3706f2962f28b8baab8842bbeef3f924c841fc4c80e4d1b2f5ad37ea243f
font_02_sfnt_off00010293.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10293 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1