Malicious PDF — malware analysis report

Static analysis result for SHA-256 de9a0bce03f1999f…

MALICIOUS

PDF

66.9 KB Created: 2021-09-28 20:01:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6aae55d4087dfbe4148d2e87ff6bf3f0 SHA-1: ed6570bd6266333a7b5a73645fe874d0bcd9bbc0 SHA-256: de9a0bce03f1999ffc02ce65a825278bbaad2b9509252f231f3f99120762604f
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF employs a common screenshot lure technique, presenting an image that requires a click to reveal its true content, which is typical for phishing or malware distribution. The presence of numerous external URIs, including one pointing to 'synerhu.ru', suggests the document is part of a link farm designed to redirect users to malicious sites. ClamAV and ML classifiers strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 66 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://synerhu.ru/uplcv?utm_term=codes+used+to+hack+phones PDF link annotation
    • https://esterkins.de/ckfinder/userfiles/files/88136710240.pdfIn PDF document text
    • https://mmrh.myagenda.cz/pictures/editor/files/fikojuratopeb.pdfIn PDF document text
    • http://zap-interactive.com/uploads/files/bizudobademegapaz.pdfIn PDF document text
    • https://www.albriug.com/static/editor/ckeditor/ckfinder/upfile/files/resosasizigaxuledani.pdfIn PDF document text
    • https://optimumquestsolutions.com/ckfinder/userfiles/files/zerixufozosikogejobifirud.pdfIn PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614fcb319a79f---73553759035.pdfIn PDF document text
    • https://mehfermobilsaglik.com/userfiles/file/buwagugazukuzogumimujuni.pdfIn PDF document text
    • https://pergamine.com/ckfinder/userfiles/files/ragepusepeje.pdfIn PDF document text
    • https://apatity.verlauf-ekb.ru/admin/ckfinder/userfiles/files/39688308191.pdfIn PDF document text
    • https://tectrongim.com/uploads/file/povapudiv.pdfIn PDF document text
    • https://franchisefarm.franchiseharbor.com/files/files/30461887280.pdfIn PDF document text
    • https://www.notusweb.com.br/ckeditor/ckfinder/userfiles/files/52633533920.pdfIn PDF document text
    • https://galaxytraining.examinationonline.com/files/zilosuvenofokopodirerejof.pdfIn PDF document text
    • https://dpengineers.info/admin/userfiles/file/rovuzuvenago.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614053bac2f8e---lawopuvofuwobowuzenarewij.pdfIn PDF document text
    • http://sarigol.kr/userData/ebizro_board/file/93009976080.pdfIn PDF document text
    • http://biosafety.biz/ckfinder/userfiles/files/pulupak.pdfIn PDF document text
    • http://cuakeobinhduong.com/upload/files/26960266967.pdfIn PDF document text
    • http://storemisr.com/uploads/files/42647586525.pdfIn PDF document text
    • http://vhktn.at/images/content/files/pevamuwuxojuniwemewusu.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_off0000a977.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA977 14068 bytes
SHA-256: 63a958e4c564cad867a894dc55491daa91c03cfd9d0bd256f815b1f27e36206d
font_01_sfnt_off0000cc6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC6A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e481.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE481 10596 bytes
SHA-256: 613150008f3bc35da74196df10cfe3ec387120581410c92f235e7e49ab5702fb