Malicious PDF — malware analysis report

Static analysis result for SHA-256 81d62d2b1fb5f546…

MALICIOUS

PDF

81.4 KB Created: 2021-10-07 03:56:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 3a4a9f8556de3124dba5e3ca84b515fd SHA-1: 4edf093cb3f2b0d623f08f3062de1706631f4a4e SHA-256: 81d62d2b1fb5f54693081a2c37ee751a314edd8a823eae64b5dee4a69b119dd7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users to malicious sites. The primary attack pattern involves luring users through these links, likely for phishing or further malware delivery.

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
  • 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://lanjutpt1.com/contents/files/dufuxikibifivixefiw.pdf In PDF document text
    • http://mos-craciun-inchiriere.ro/fckfiles/file/74445798280.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/d17788084ba147ce70d8ae345c046d8f/rimilanaxijebugudisupiwum.pdfIn PDF document text
    • http://taborgospelassembly.com/userfiles/file/wazijabate.pdfIn PDF document text
    • http://globalnetworks.de/www.galabau-poscher.de/main/preview/ckfinder/userfiles/files/dazusipitefit.pdfIn PDF document text
    • http://cbcom.fr/ressource/site-image/files/47756281820.pdfIn PDF document text
    • http://local-minicab.com/survey/userfiles/files/9831065490.pdfIn PDF document text
    • http://norilsk.torbay.ru/images/uploads/file/lakatexamoxegomatudabe.pdfIn PDF document text
    • http://wpklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/rafut.pdfIn PDF document text
    • https://markmont.eu/editor_uploads/system/files/tivalumoronipo.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137e1b3304f3---tazoxutenufo.pdfIn PDF document text
    • https://yourtuscanyguide.com/wp-content/plugins/super-forms/uploads/php/files/vqk9g59fs461vmnjlhu9bvnm93/13770157964.pdfIn PDF document text
    • http://oikoscoccatoarchitettura.com/userfiles/files/64535189157.pdfIn PDF document text
    • http://laboratoriodiprogettazione-ve.it/userfiles/files/79021395935.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134af667d73d---muwatuv.pdfIn PDF document text
    • https://tuabogadoangel.com/wp-content/plugins/super-forms/uploads/php/files/3dcb618ecfc71e9638126fdef872425f/39648783855.pdfIn PDF document text
    • http://sake2metustin.com/uploads/files/sajegejataf.pdfIn PDF document text
    • http://omatsuri.kr/data/userfiles/files/8519678851.pdfIn PDF document text
    • http://cameranichietsu.com/luutru/files/jutefov.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/161408ed941c64---15018665968.pdfIn PDF document text
    • http://kiavysocina.cz/UserFiles/File/fesibatalulaniwi.pdfIn PDF document text
    • https://ego-sofa.tw/uploads/files/202109171815487306.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/5371804b934272681ca6f775a9b62101/pikubepitakevokaziril.pdfIn PDF document text
    • http://veiligheidsslot.nl/ckfinder/userfiles/files/lominiwonexebaredozafewe.pdfIn PDF document text
    • https://vanvoorst.info/uploaded/file/xovubibaredagagonefoju.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=put+yourself+out+there+synonymPDF 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_off0000da85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA85 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f29c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF29C 10440 bytes
SHA-256: 3414f9627d52e999ae005bd9bd8096aa623e7834574a16a2199f41e39dcc56c7
font_02_sfnt_off00010a2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A2C 17736 bytes
SHA-256: f5e541db84912c96b0a9ac04c531918ff33d3c1131003becabce89917083f7a2