Malicious PDF — malware analysis report

Static analysis result for SHA-256 178e93b3a801f4c4…

MALICIOUS

PDF

69.4 KB Created: 2021-10-02 12:33:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 349aa649197a6d72570e79bb22bdb421 SHA-1: 92901ea96aa2ce8ef23fbdb9d5ed3646b1ac943a SHA-256: 178e93b3a801f4c4bd7e2cdac516d2fa56679455007a4abc9211571a2d91814d
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The document body is heavily obfuscated and unreadable, but the heuristic firings clearly point to a malicious link distribution pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://medvor.ru/uplcv?utm_term=how+to+make+brown+colour+with+other+colours PDF link annotation
    • https://charlesstreetvideo.com/userfiles/file/84822337307.pdfIn PDF document text
    • http://maturitni-ples.eu/UserFiles/File/32500715624.pdfIn PDF document text
    • http://vegman-kzn.com/ckfinder/userfiles/files/42034994052.pdfIn PDF document text
    • https://heyratacademy.ir/file/pexosi.pdfIn PDF document text
    • http://studiotecniconuti.it/userfiles/files/butivejilubitup.pdfIn PDF document text
    • https://harom.ro/files/file/wigepanejamugizebana.pdfIn PDF document text
    • http://laconchigliacasevacanze.it/userfiles/files/38758501809.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/vv5lgnstdfc00sbrmqo8g68kli/91228219137.pdfIn PDF document text
    • http://www.ecostroyservis.ru/File/74817396674.pdfIn PDF document text
    • http://www.fashiongale.ro/userfiles/files/tosog.pdfIn PDF document text
    • http://mlsconsulting.net/cms/files/File/78004153702.pdfIn PDF document text
    • http://ctnphrae.com/ckfinder/userfiles/files/zasasaxotitudix.pdfIn PDF document text
    • http://ctcinsulator.com/uploads/file/gitaxubi.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d1675ae7a0---nojogefanajafexavu.pdfIn PDF document text
    • https://maintogelonline2.bet/contents/files/78518152047.pdfIn PDF document text
    • https://arbormaster.net/uploads/files/davarinegepad.pdfIn PDF document text
    • http://allineers.morefriendship.com/upload/files/vopafozeboso.pdfIn PDF document text
    • https://www.bmo-agencement.fr/ckfinder/userfiles/files/14250531328.pdfIn PDF document text
    • http://shahgrp.com/uploads/20510909106.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16156460c24a86---28599081469.pdfIn PDF document text
    • http://yucehukuk.com/resimler/files/78333897699.pdfIn PDF document text
    • https://sbmhavacilik.com/userfiles/file/kixezonez.pdfIn PDF document text
    • http://kaiyudachem.com/filespath/files/20210903082148.pdfIn PDF document text
    • http://xn--djr00fsyfv0o5qgy9u.net/filespath/files/20210911144731.pdfIn PDF document text
    • https://supportsystemsvainc.com/home/ssvi/public_html/ckfinder/userfiles/files/16178970410.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_off0000b2dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2DD 10904 bytes
SHA-256: 039d40c67d1039db6d68c56e376103d2c359796470be3b2a7e092f985c5b665d
font_01_sfnt_off0000cbe2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBE2 14300 bytes
SHA-256: 54ba0e38eb2ecf516edeba3d84c68dad0245296a413fda733c2a157519269619
font_02_sfnt_off0000ef56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF56 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1