Malicious PDF — malware analysis report

Static analysis result for SHA-256 f0b04a67703d0104…

MALICIOUS

PDF

87.4 KB Created: 2021-09-05 14:16:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 9f7bbabdaeba52f19f4e157dca6c5ad9 SHA-1: 4f789cba00013193e9ca5dd4b8c8021026b6b6c0 SHA-256: f0b04a67703d0104bbc2b81f4f760fc0ebd69ec13cc059508f30e1d170e76d24
156 Risk Score

Malware Insights

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

The PDF file contains numerous links, many pointing to compromised WordPress upload directories and disposable hosting domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is heavily obfuscated and contains metadata from wkhtmltopdf, suggesting it was programmatically generated to host these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 https://capitalsyndic.com/userfiles/file/88191801665.pdf In PDF document text
    • https://thefertilizerequipment.com/d/files/55573049412.pdfIn PDF document text
    • http://heibldr.hu/FCKfeltoltott/file/48043645908.pdfIn PDF document text
    • http://vigova.com/Images_upload/files/61032392466.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/rasapuwiwegodazad.pdfIn PDF document text
    • https://binhvi.com/upload/files/ronemikowova.pdfIn PDF document text
    • https://keyseries.us/userfiles/file/vokiwe.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/ea2b1d423addd4fe11c944cded930635/99725211634.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/16099c6298e7c2---63941701893.pdfIn PDF document text
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/fbe47d1ee6791b70dadaaa8d16ac8dc9/37119984533.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160a974d2b577d---lefubalijojexumofiso.pdfIn PDF document text
    • http://ntouioc.ntou.edu.tw/ckfinder/userfiles/files/koxowopejixetezawosaz.pdfIn PDF document text
    • https://stalbeckers.nl/userfiles/image/file/wofanutefowebizabor.pdfIn PDF document text
    • http://csim.jp/ckeditor/uploads/files/pebulobakusinujo.pdfIn PDF document text
    • https://lastcallslc.com/wp-content/plugins/super-forms/uploads/php/files/b1414b3341a25f12b1f08e85afbadd12/kolokaxive.pdfIn PDF document text
    • http://www.parkwaytransplant.com/media_upload/upload/files/rejikafala.pdfIn PDF document text
    • https://eingangrad.ch/userfiles/files/87761315134.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c2893138397---webasajanufikadosapifo.pdfIn PDF document text
    • https://techielingo.com/fck_uploads/files/1282648710.pdfIn PDF document text
    • https://mimpishiosatu.com/contents//files/wumixomudafajole.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/c9fe227995c7c842773dde22eef64983/gawiwevakilamomoronigekaf.pdfIn PDF document text
    • http://gestaocipa.com/public_html/Imagens/file/66328489421.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=krakow+tourist+map+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://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_off0000ef1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF1D 18620 bytes
SHA-256: fbb77659a6d763db9d4a39a5d40fd4fb034ab9a0351e763212f006a26a904c5d
font_01_sfnt_off00011f99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F99 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000137b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137B0 10648 bytes
SHA-256: 1bfaa4d0a5af5cd06fec4e4b882a97ef1c33ec9549be737ebe7094fd7889ed3f