Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d3c11d4fa15f55f…

MALICIOUS

PDF

79.9 KB Created: 2021-10-03 16:26:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 0ca5148202ad078bedcc15d16b6afcb8 SHA-1: a6ecabdd7698dd2d752e06655938fb590201f973 SHA-256: 5d3c11d4fa15f55fb555ba44dc4ed5b307d9d69e72fcbacb746e7dfbe2864b5a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous embedded URLs pointing to external sites, many of which are PDFs themselves, suggesting a multi-stage download or redirection scheme. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links, further supporting a malicious intent to obscure the true destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://huntic.ru/uplcv?utm_term=how+to+mix+teal+with+acrylic+paint PDF link annotation
    • http://lamardaegu.com/upfile/user/file/niveruj.pdfIn PDF document text
    • http://yalcinsezer.com/upload/ckfinder/files/kazuxixifavasas.pdfIn PDF document text
    • https://fnb-concepts.com/images/uploads/files/vobej.pdfIn PDF document text
    • http://rosesrealtyhomes.com/userfiles/files/zeriwagaxaveju.pdfIn PDF document text
    • https://vnmmalta.com/userfiles/file/38571323241.pdfIn PDF document text
    • https://bloomlight.pl/_bloom/file/89198369850.pdfIn PDF document text
    • http://profiklub.sanswiss.cz/files/file/71845001726.pdfIn PDF document text
    • http://7seapharmtech.com/Uploadfiles/files/53771363071.pdfIn PDF document text
    • http://ondrejkocar.cz/img/file/nijutabatakawikizedipu.pdfIn PDF document text
    • http://gelateriacool.it/userfiles/files/72628714848.pdfIn PDF document text
    • https://zoomkish.com/basefile/zoomkishcom/files/zidaporevobivaxa.pdfIn PDF document text
    • https://catbasailing.com/upload/fck/file/13665845283.pdfIn PDF document text
    • http://hansungid.com/userfiles/file/fuvomeluxe.pdfIn PDF document text
    • https://topclassgreenery.nl/images/file/47416943667.pdfIn PDF document text
    • http://huonglonghotel.com/uploads/image/files/6919331734.pdfIn PDF document text
    • http://www.adarshvidhyasankul.org/userfilesfile/58765030758.pdfIn PDF document text
    • http://enotecagaribaldi.it/userfiles/files/76334616670.pdfIn PDF document text
    • http://www.evisiontiendaonline.com/ckfinder/userfiles/files/rosezomiz.pdfIn PDF document text
    • http://asia-test.informacittadino.net/media/files/dipat.pdfIn PDF document text
    • http://azbuka-d.ru/ckfinder/userfiles/files/vulegobadilatanafozop.pdfIn PDF document text
    • http://heryeryesil.com/resimlerfiles/91100774573.pdfIn PDF document text
    • http://zussobrance.sk/grafika/dokumenty/raxegivajivaxogox.pdfIn PDF document text
    • http://househouse.it/userfiles/files/51824622586.pdfIn PDF document text
    • http://ytovietnam.net/ckfinder/userfiles/files/solipuvojubosevupudo.pdfIn PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142781b1d9c4---xodabujowogunesatijo.pdfIn PDF document text
    • http://prospekt-rostov.ru/ckfinder/userfiles/files/kixixu.pdfIn PDF document text
    • http://elma1.ru/!upload/files/jupusitoxubofaronuvuterij.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_off0000cd20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD20 10764 bytes
SHA-256: 0cab8443ca892dd551626f86fd3e13f6c12db5c082fc26572dc70f41a8567169
font_01_sfnt_off0000e5b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5B2 20148 bytes
SHA-256: 1a846fa3d85eb48442329a65b1d2d9f7183f4e9190a703846f48e8646765ebcd
font_02_sfnt_off0001199f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1199F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1