Malicious PDF — malware analysis report

Static analysis result for SHA-256 39cd0f26eb8939a4…

MALICIOUS

PDF

72.4 KB Created: 2021-09-10 19:43:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8b74c08d73059417a5777a2e9e3454c8 SHA-1: 406959250d4434a7592da822b44195f3eb4c3149 SHA-256: 39cd0f26eb8939a4f0651c4297bcb936bc97c8a64344db3d4f11001a666fc075
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm. The document body is heavily obfuscated, but the presence of numerous embedded URLs suggests an attempt to redirect the user to malicious content. No scripts were extracted, but the PDF structure itself is likely exploited.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://maturana.cl/upload/file/7165343972.pdf In PDF document text
    • https://webkapper.nl/ckfinder/userfiles/files/58760819986.pdfIn PDF document text
    • http://hemeringen.de/ckeditor_ablage/userfiles/files/kabagusokutoresenutuvig.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/108214dfd8e45c902cc691e625c660eb/42692979558.pdfIn PDF document text
    • http://hoangnampte.vn/quangbasanpham/app/webroot/upload/image/files/wawoduxotilakoj.pdfIn PDF document text
    • https://institut-arabe.org/ckfinder/userfiles/files/dodokewopipemobijoledidu.pdfIn PDF document text
    • https://dakotaterritorydevelopment.com/ckfinder/userfiles/files/babalalodeji.pdfIn PDF document text
    • http://gmkms.net/upfile_editor/2021/files/nulavumiwejavuguzanab.pdfIn PDF document text
    • http://whitedwarf.ru/public/images/ckfinder/files/85092656688.pdfIn PDF document text
    • http://dachastyle.com/userfiles/file/zugaj.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021090920115964.pdfIn PDF document text
    • http://2girlstrippin.com/wp-content/plugins/formcraft/file-upload/server/content/files/161362cb368461---mujasozogidiwotoxosuju.pdfIn PDF document text
    • http://tochalco.com/uploads/files/tifukovowufazovuro.pdfIn PDF document text
    • http://kanchanaspa.com/ckfinder/userfiles/files/59517472718.pdfIn PDF document text
    • https://atputasbaze.lv/images/userfiles/files/guremum.pdfIn PDF document text
    • http://graczeonline.pl/userfiles/file/7405941743.pdfIn PDF document text
    • http://0vote.com/ckfinder/files/jejepapaxu.pdfIn PDF document text
    • http://kreativitaet-stadlhofer.at/global/images/userfiles/file/31458477875.pdfIn PDF document text
    • https://bdlvn.com/steel/upload/files/mijameza.pdfIn PDF document text
    • https://letajicikoberce.cz/userfiles/file/topumevevagemixerizabafa.pdfIn PDF document text
    • http://hindel-relax.ch/ckfinder/userfiles/files/25839646776.pdfIn PDF document text
    • https://ruh-center.ru/userfiles/file/gesaw.pdfIn PDF document text
    • http://www.premiumimport.nl/ckfinder/userfiles/files/13453581639.pdfIn PDF document text
    • http://pekingtogo.com/uploads/files/43424743715.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=how+to+make+android+private+numberPDF 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_off0000b9e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9E4 10816 bytes
SHA-256: 0b1a90c315f1278052e58228b20fbe11a40c78eeee5ca52b420093cd3bf75919
font_01_sfnt_off0000d287.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD287 16288 bytes
SHA-256: 14f223e343e39deeec5d2916edb1ad18eccd00a0115992ae6729c0675234d743
font_02_sfnt_off0000fbe9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBE9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1