Malicious PDF — malware analysis report

Static analysis result for SHA-256 f94661bd8b47915d…

MALICIOUS

PDF

91.0 KB Created: 2021-09-24 01:46:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: bf3c5683642a6b83113ae2a4a1ac1344 SHA-1: 20541ca39291272faed279c4467630e0ced92bff SHA-256: f94661bd8b47915d80a7938827b6c8669c603a158db73cf04999b5e7250a11df
174 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it uses a browser installation lure to trick users into installing malicious software. While no scripts were directly extracted, the PDF structure and embedded URLs suggest it is designed to download and execute a second-stage payload, likely exploiting a vulnerability or tricking the user into running it.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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.
  • 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 http://www.mattig-accounting.bg/fisiere/file/72369632699.pdf In PDF document text
    • http://sung1.com/upload/files/worukulaxafotelepapizon.pdfIn PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613a03543931f---mexarak.pdfIn PDF document text
    • http://polyacer-ecp.com/userfiles/files/20210915_091755.pdfIn PDF document text
    • http://snft.ro/media/file/vozawipakemujo.pdfIn PDF document text
    • http://cuoredicane.it/userfiles/files/lerifisesexobexuredakuz.pdfIn PDF document text
    • http://koutingchina.com/upload/files/susedo.pdfIn PDF document text
    • http://it-hair.com/userfiles/15466846234.pdfIn PDF document text
    • https://jeevandeepspecialcare.com/ckeditor/ckfinder/userfiles/files/vifabunovuripewigewolu.pdfIn PDF document text
    • https://serka.com/serka/upload/files/jakuwuduvokemar.pdfIn PDF document text
    • http://archgeo-leszno.pl/uploads/userfiles/files/25037449535.pdfIn PDF document text
    • https://china-glass-mosaic.com/userfiles/files/20210912_225105.pdfIn PDF document text
    • https://asesoriagade.com/app/webroot/files/files/tufed.pdfIn PDF document text
    • https://taumed.kz/upload/2021/09files/210921171433899449dnx2v.pdfIn PDF document text
    • http://freetourscadiz.com/ckfinder/userfiles/files/97167594253.pdfIn PDF document text
    • http://zamaro.info/images/fcke_files/file/93143209047.pdfIn PDF document text
    • http://balashixa.inhome360.ru/admin/ckfinder/userfiles/files/20922721502.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ff8a3cda15---xegedosawova.pdfIn PDF document text
    • http://indagosrl.it/userfiles/files/87111369470.pdfIn PDF document text
    • http://jongauger.com/userfiles/file/zufefazinuxolej.pdfIn PDF document text
    • https://dazhonghua1688.com/ckfinder/userfiles/files/66241202198.pdfIn PDF document text
    • https://rumputhijau.com/contents/files/68793779711.pdfIn PDF document text
    • https://recapress.com/ckfinder/userfiles/files/92775706425.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=avg+antivirus+pro+android+keyPDF 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_off0000ee12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE12 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010624.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10624 16660 bytes
SHA-256: c451ee6137962628cae8a4ea866a7265df25be9867cf7990777a811ee6971322
font_02_sfnt_off000130ac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130AC 17684 bytes
SHA-256: c56c9b12ff36f71e6f7ca5c7e01f97140558f3c21a3165dbcc425e7ca9ccc87c