Malicious PDF — malware analysis report

Static analysis result for SHA-256 938c441c33b0589e…

MALICIOUS

PDF

71.1 KB Created: 2021-09-26 11:11:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 8b3accb26ed7a52b9bbab87a4b049de1 SHA-1: b986d76fb3c4ec67f3eb206a4cc74273d5d90eab SHA-256: 938c441c33b0589ea4a0162ee43c7186ab940112b5b63f5ed8921f5c0bebf423
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to PDF files hosted on disposable domains, suggesting a link farm for distributing malware. The 'SE_PASSWORD_ARCHIVE_LURE' heuristic indicates the document likely instructs users to open a password-protected archive, a common tactic to bypass gateway scanning. ClamAV detection and ML classification confirm its malicious nature. While no scripts were directly extracted, the PDF structure and link farm behavior are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://pixomot.ru/uplcv?utm_term=how+to+draw+lungs PDF link annotation
    • http://j1medical.com/uploaded/file/gonuraji.pdfIn PDF document text
    • http://privateeducation.sg/verzsape/demo/upload/admin/files/xuxirovujodazumirosodax.pdfIn PDF document text
    • http://www.tempshift.com/app/webroot/files/uploadimagesfile/gekowetafafejibo.pdfIn PDF document text
    • http://branpc.in/ckfinder/userfiles/files/27959509620.pdfIn PDF document text
    • http://bright-mineral.com/uploadfile/file/2021090412044014.pdfIn PDF document text
    • https://xn--80aggmy8c6c.net/UserFiles/File/22652511869.pdfIn PDF document text
    • http://townofwinslowin.com/flash/townofwinslowin.com/file/55272743411.pdfIn PDF document text
    • http://primaria-ciocirlia.ro/media/file/35273984195.pdfIn PDF document text
    • http://e-skala.pl/userfiles/file/xudoxotinibi.pdfIn PDF document text
    • https://manusingh.org/scgtest/eec-new/codelibrary/ckeditor/ckfinder/userfiles/files/17175756157.pdfIn PDF document text
    • http://exosushi.com/uploads/files/11099397154.pdfIn PDF document text
    • http://taxplus.in/images/contentimages/files/sowefutixagajakeselomenuk.pdfIn PDF document text
    • http://gruppocinofilomarsalese.com/userfiles/files/36025033111.pdfIn PDF document text
    • http://mail.me.ntou.edu.tw/ckfinder/userfiles/files/20210918_071918.pdfIn PDF document text
    • http://cinstech-inspect-survey.com/fckeditor_userfiles/file/94042455759.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1612fee7c90322---83627301360.pdfIn PDF document text
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/78514e7b6d0825c9c124fe99dada5819/53171821355.pdfIn PDF document text
    • http://tech-sub.com/userfiles/file/31780399414.pdfIn PDF document text
    • http://emanuelmlevin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/11068965997.pdfIn PDF document text
    • https://mudraconsultancy.com/uploads/files/21127140202.pdfIn PDF document text
    • http://apvn.info/userfiles/file/zafizipakaf.pdfIn PDF document text
    • http://radio-salsa.com/php/rs/filesupload/file/letevazobalozewafenej.pdfIn PDF document text
    • http://ysenb.kr/board/file/editor/file/13778026580.pdfIn PDF document text
    • https://bestcaps99.com/ckfinder/userfiles/files/vavufujuv.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_off0000b4e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4E0 16900 bytes
SHA-256: 582caafb5469e18db24b0dd76b938abb78f6c46702742ef82b870a8c46554cd3
font_01_sfnt_off0000dfaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFAF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f7c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7C6 10376 bytes
SHA-256: 1db4a080d8a306da059b44a60b00f58599a3ceaf2c56000db199b7f43a4cf29f