Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e8c9d22e7d7cb79…

MALICIOUS

PDF

85.7 KB Created: 2021-09-21 05:21:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b8da1afdefa41da948a1be9f166173f0 SHA-1: 03ce9ebab52a99cd74cbeae5301b2f1ba4fa659a SHA-256: 8e8c9d22e7d7cb79c3576630dc544f53b86fad453e6c549e418c6068f035b5c0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains numerous embedded URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting it functions as a link farm to distribute malicious content. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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
  • 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://huntic.ru/uplcv?utm_term=how+to+stop+group+tabs+in+chrome+android PDF link annotation
    • http://fthyhs.com/resource/docContentImg/file/2021-09-16/9914cdee03f8479b03abb62750ab66a2.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132ffa83b1c0---76464056854.pdfIn PDF document text
    • http://rtm-plus.ru/ckfinder/userfiles/files/32696607622.pdfIn PDF document text
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/7ac850a73bdc9ee9b8cc3f130bc69675/wimulogogede.pdfIn PDF document text
    • https://trompis-tondschungel.de/userfiles/file/51753261224.pdfIn PDF document text
    • http://araulmor.tel-cor.com/images/library/file/45450146459.pdfIn PDF document text
    • http://dailyliving.nl/ckfinder/userfiles/files/boruvuzomorifopiv.pdfIn PDF document text
    • https://www.prieur-equipement.com/ckfinder/userfiles/files/62984610981.pdfIn PDF document text
    • https://tlproduct.com/userfiles/file/41155471696.pdfIn PDF document text
    • http://ydchem.cn/filespath/files/20210905134406.pdfIn PDF document text
    • http://saeronbio.com/userData/board/file/defemuwanetuxigivadozewid.pdfIn PDF document text
    • http://wingmanplanningdemo.com/userfiles/files/22324135263.pdfIn PDF document text
    • https://kovrdom.ru/sites/all/sites/default/files/file/kozexojurige.pdfIn PDF document text
    • https://textosolutionslinguistiques.ca/upload/editor/file/87498810602.pdfIn PDF document text
    • http://a2itsolutions.com/chop/multimedia/userfiles/file/winawevegajatoge.pdfIn PDF document text
    • https://thuaphatlaihanoi.net/uploads/files/47550994290.pdfIn PDF document text
    • https://www.leadercaravans.com.au/application/third_party/ckfinder/userfiles/files/42555392094.pdfIn PDF document text
    • https://bibliotheque.ville.deux-montagnes.qc.ca/ckfinder/userfiles/files/fukeguxabujugenunu.pdfIn PDF document text
    • http://www.puhito.hu/uploads/ditotaka.pdfIn PDF document text
    • http://luxmeterthai.com/ckfinder/userfiles/files/kibazisarurozimatufuvagaz.pdfIn PDF document text
    • https://skywaytravelandholidays.com/ckfinder/userfiles/files/mogomemadawufomexapiz.pdfIn PDF document text
    • https://big-affaires.com/img/pics/files/tuforigunizowe.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161438cffe83f8---mefubobusu.pdfIn PDF document text
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/c04a2b0e4f0ddc252a5d75b85e528073/toxedamikuniditamokuwupap.pdfIn PDF document text
    • http://nexxosrealty.com/userfiles/files/82872436822.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_off0000ea69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA69 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010280.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10280 11232 bytes
SHA-256: 933972de0379d54b92c238df5ea86a42411b6f94a88c2b88c46f5a64584f8fca
font_02_sfnt_off00011c3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C3E 17336 bytes
SHA-256: 0cc3dca5626d22b9326213bccf743f9a5de647aefc5689368010b4fcf21c1bbb