Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d5dddb19c64fe81…

MALICIOUS

PDF

100.4 KB Created: 2021-06-23 23:53:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 9ee162d28793ef17ee6224cbe7d29d23 SHA-1: fcd28760184d8beb6e41692753f73ea5be43fba5 SHA-256: 8d5dddb19c64fe8152bc27afce3680bdd9e05b32edacc5ee4640c3a8b983cc7b
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. While no scripts were directly extracted, the PDF structure and link farm heuristic point towards an attempt to lure users to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/e41ac189647a13c5c66ea6382f493ead/10560183532.pdf In PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607c114b137ae---vivosixoxuzuzip.pdfIn PDF document text
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/e5ed21c5c1c63fcb8fd35654ef64d36c/kofeviperolipuwowumobifir.pdfIn PDF document text
    • http://www.motorradfreunde-toggenburg.ch/up/files/boxobodupemozabolus.pdfIn PDF document text
    • https://deesudcoolingtower.com/userfiles/file/57757616960.pdfIn PDF document text
    • http://bajajsports.com/userfiles/file/86341222880.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/098875e23636e9047f038946473146b0/45257160150.pdfIn PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/50af1a4b374a52a935d8a4c4dff70348/98937457827.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16071453cade30---fadoxaxasasadejidebifovos.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/160948881a0593---39389468899.pdfIn PDF document text
    • http://zoncmswebsitebeheer.nl/files/editor/file/wezed.pdfIn PDF document text
    • https://okinawa4d.com/contents//files/20790441461.pdfIn PDF document text
    • http://allprintusa.com/admin/images/file/71866339599.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/c3d986e4c579e131d674d7430e3037ad/26363673656.pdfIn PDF document text
    • http://adabaskimerkezi.com/upload/file/53568343308.pdfIn PDF document text
    • http://af.ssla.ru/images/fornews/files/pilan.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=play+group+class+books+pdfPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00013e4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E4A 5160 bytes
SHA-256: b74f0e48d84b15aeec9ca267ad066be4f3d9c54ec9b99224d2fd4454d68761fd
font_01_sfnt_off00014fdf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14FDF 11456 bytes
SHA-256: 5c183fe70fc538b73363c055acb951aa2c7d3f6692c33465000b5721226cd211
font_02_sfnt_off000176c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x176C7 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378