Malicious PDF — malware analysis report

Static analysis result for SHA-256 739d8f944dfdb35e…

MALICIOUS

PDF

72.7 KB Created: 2021-09-08 22:09:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: dcf18e8e8e457dc1980be9f8575d6095 SHA-1: f535a919c499a68a971c6de393500fb02ae69625 SHA-256: 739d8f944dfdb35e4c7a19120007748d4cb8c33d94262c543ec054e5d0371c98
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, indicating an attempt to redirect the user to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery via the linked URLs. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports the malicious nature by identifying a pattern of disposable hosting for links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://synerhu.ru/uplcv?utm_term=y2mate+pro+apk PDF link annotation
    • http://macro-e.com/app/webroot/userfiles/files/wirivumugemupeponeguwux.pdfIn PDF document text
    • http://safiorida.nl/operatori/userfiles/file/tekedug.pdfIn PDF document text
    • http://nanobubblevietnam.com/uploads/userfiles/file/zositobasugatanuxemomu.pdfIn PDF document text
    • http://hondatayho.vn/images/ckeditor/files/vojididelojik.pdfIn PDF document text
    • http://salespate.com/userfiles/file/jupowuw.pdfIn PDF document text
    • http://www.verneteco.com/ckfinder/userfiles/files/kolirevozimupizimesazud.pdfIn PDF document text
    • http://www.ondebiz.com/userfiles/file/40087912476.pdfIn PDF document text
    • http://leebyunghun.org/new/upload/board/files/24653152670.pdfIn PDF document text
    • http://topimmigrationlawyer.org/ckfinder/userfiles/files/suxurobanijifezawan.pdfIn PDF document text
    • https://inunekocp.jp/mailmagazine/upload/files/95770552681.pdfIn PDF document text
    • http://taiwan-tsai.com/upload/files/putoxodemef.pdfIn PDF document text
    • https://millvalley.com/wysiwygfiles/file/70384865037.pdfIn PDF document text
    • http://glamour-nsk.ru/ckfinder/userfiles/files/287616466.pdfIn PDF document text
    • http://stcforanebanglore.smcim.com/www/js/ckfinder/userfiles/files/95228964467.pdfIn PDF document text
    • http://umbabox.com/userfiles/file/10477178803.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16135337d01953---livogopezanojogulupan.pdfIn PDF document text
    • http://orbitsecurity.qa/pro_mvp_tech/uploads/file/buberizapiko.pdfIn PDF document text
    • http://kirakuramenandsushi.com/uploads/files/vomuderegozajavunejata.pdfIn PDF document text
    • http://cbafjvn.com/uploads/userfiles/file/rozadazuvijijuresopakeku.pdfIn PDF document text
    • https://legacydockandmarine.com/wp-content/plugins/super-forms/uploads/php/files/5462887566a9a6f8024d23397f256ca0/37531327333.pdfIn PDF document text
    • https://billionbosses.com/ckfinder/userfiles/files/78557742698.pdfIn PDF document text
    • http://razaviota.ir/basefile/razaviotair/files/53557429457.pdfIn PDF document text
    • http://ecme.site/2015/vat/upload/files/44046051865.pdfIn PDF document text
    • http://zssadkowice.pl/pliki/nojezuro.pdfIn PDF document text
    • http://ddaengshop.com/ckupload/files/61739465437.pdfIn PDF document text
    • 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_off0000bc40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC40 10200 bytes
SHA-256: eedc6655b67de8ba75b9f629836c4d141a82de620c5e9319fedb9290e8a9ddee
font_01_sfnt_off0000d32d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD32D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eb3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB3F 16324 bytes
SHA-256: c052fd525d17dc47c30097d5872b98abfbd5b07a0ba74defba48ff51a2b903b5