Malicious PDF — malware analysis report

Static analysis result for SHA-256 518ee69d65b64a09…

MALICIOUS

PDF

93.7 KB Created: 2021-09-19 09:07:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 9f42caefd6524228e94424d624679570 SHA-1: 2aa6216745b021989b12f4a15d938c30c8eb4b35 SHA-256: 518ee69d65b64a09525d5000269ccc46d2942d3a2338b0c23a7dbbcd5bd736a3
182 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains embedded JavaScript and multiple external URLs, indicating it is designed to lead the user to a malicious download or exploit. The 'Fake CAPTCHA' heuristic strongly suggests a social engineering tactic to trick the user into executing a payload. The ML classifier and ClamAV detection further support its malicious nature, likely as a phishing or trojan delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://chcial.ru/uplcv?utm_term=law+books+in+marathi+pdf PDF link annotation
    • http://pate4me.com/userfiles/file/likikuparofap.pdfIn PDF document text
    • https://www.pu-sk.com/app/templates/js/ckfinder/userfiles/files/75459254103.pdfIn PDF document text
    • https://momentous-inst.com/uploads/image/files/nijexemekizurirulojurera.pdfIn PDF document text
    • http://aotwcasino.com/ckfinder/userfiles/files/davopatazoxuziko.pdfIn PDF document text
    • http://shijijiaming.cn/filespath/files/20210919074755.pdfIn PDF document text
    • http://uitetenindex.nl/images/uploads/kemafazaratedonuvitafure.pdfIn PDF document text
    • http://studioarchoggianiepartners.it/userfiles/files/raziviwetegijiru.pdfIn PDF document text
    • http://om-ar.com/userfiles/file/260507911.pdfIn PDF document text
    • http://4bx.pl/public/file/96080074220.pdfIn PDF document text
    • https://speakingparrot.com/upload/ckfinder/files/36593149124.pdfIn PDF document text
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/60620094187.pdfIn PDF document text
    • https://marcuspietrek.de/MARCUS/files/file/lefufazinuneratijenumodo.pdfIn PDF document text
    • http://checopharma.com/upload/files/61855094738.pdfIn PDF document text
    • https://signos.larrialdiak.es/files/galeria/files/tinupoduza.pdfIn PDF document text
    • http://cedule-plachty.cz/files/file/kofolajo.pdfIn PDF document text
    • http://valosagoskincsesbanya.com/upload/file/zopataxupojigoputule.pdfIn PDF document text
    • http://algarestofos.pnh.pt/js/ckfinder/userfiles/files/gozalafulosuxugi.pdfIn PDF document text
    • https://ezastupitelstvo.sk/editor_uploads/system/files/jikimadit.pdfIn PDF document text
    • http://lsbwg.com/ckfinder/userfiles/files/20210910/1930573589.pdfIn PDF document text
    • http://newbiesites.com/userfiles/file/zagomokiwo.pdfIn PDF document text
    • https://thietkewebseo.com/webroot/img/files/bujobugibatezepivaj.pdfIn PDF document text
    • http://stefanourso.com/public/userfiles/file/7384632877.pdfIn PDF document text
    • http://xn--dlek-5qa.com/admin/UserFiles/file/70642808547.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_off000106f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106F8 10860 bytes
SHA-256: 517642b080670b89113fc02e175307d1f3e61cba1d0a487731b9667a38184c50
font_01_sfnt_off00011fb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FB1 18892 bytes
SHA-256: c90084c59a47487c92517eeec8821bd0d9ee843d363b33e2a6ea6760beeacb6c
font_02_sfnt_off00015104.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15104 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1