Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd91b7d2ad97270f…

MALICIOUS

PDF

82.8 KB Created: 2021-09-19 08:05:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4ef80efc672f30ed1b072975acccf752 SHA-1: bee4fb1f5cf6b3dd4b9684783850d488705ea299 SHA-256: fd91b7d2ad97270f58d46ab8998cc8be49fdbf534c8eb5f38c9adfb1b9708dc4
156 Risk Score

Malware Insights

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

The sample was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics indicate the PDF acts as a link farm, directing users to compromised websites and disposable hosting, likely for phishing or malware distribution. The presence of multiple PDF link farm indicators and the ML classification strongly support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://eurouniversal.eu/ckfinder/userfiles/files/82448942801.pdf In PDF document text
    • https://akproauto.net/nbloom/fckuploads/file/14353903219.pdfIn PDF document text
    • http://szyoujin.com/UploadFile/file/20210908142713376.pdfIn PDF document text
    • http://hzxf.com/images/upload/File/35831979158.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/e79d8a5bfa47190ac49354d22496856a/15867249847.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161407715260f0---muzusogabujekiwevezu.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/nedekinasezabe.pdfIn PDF document text
    • http://tochuchoinghi.org/files/37817899819.pdfIn PDF document text
    • https://gulf-rope.com/images/bulk_images/files/69502799013.pdfIn PDF document text
    • http://www.mariabeckmann.com/fotos/uploads/files/sovekil.pdfIn PDF document text
    • http://lateonsettay-sachs.org/userfiles/file/liwesevafadofabepilaz.pdfIn PDF document text
    • http://eternoohydro.com/d/files/85752749738.pdfIn PDF document text
    • http://weforyou.it/userfiles/files/xojab.pdfIn PDF document text
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613206d841730---tamenij.pdfIn PDF document text
    • https://bbu.vn/Images_upload/files/15196566257.pdfIn PDF document text
    • http://sualpturizm.com/userfiles/file/zukadimudidovitetuzadubub.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/56172475916.pdfIn PDF document text
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1613ed80d78e6b---80828788242.pdfIn PDF document text
    • https://sanagustin.cl/files/widofakikolafem.pdfIn PDF document text
    • http://hueide.com/upload/files/kekoza.pdfIn PDF document text
    • https://licorne-hotel-restaurant.com/userfiles/file/zelara.pdfIn PDF document text
    • http://josephfellerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fizodokibevu.pdfIn PDF document text
    • http://ysmenmidwestindia.org/uploads/userfiles/file/file/32204539616.pdfIn PDF document text
    • https://telorgabus.com/contents/files/43762332553.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=fifty+shades+of+grey+online+streamPDF 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_off0000dd36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD36 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f54d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF54D 10892 bytes
SHA-256: 4fb4d83353ce61152d3a43636d651f328c303926f5996cec4c66f842a545980f
font_02_sfnt_off00010e0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E0E 18132 bytes
SHA-256: d360656ddcbc17e01a0091bf652df16ca9fe655d34e6698be556b806fd61307e