Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c9b89faa6c01984…

MALICIOUS

PDF

81.1 KB Created: 2021-09-14 10:35:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: e877fa276789008766d0e40f0c250a9b SHA-1: eccbe0292451c4ea1a98be97ee62c8e80c9898c4 SHA-256: 9c9b89faa6c01984270ad8a6d93dfa776189a1e1c1e91161197d21bbce46dbc2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, specifically identified as a phishing trojan by ClamAV. It contains a link farm that directs users through compromised CMS uploads and disposable hosting, likely to a phishing or malware distribution site. Although no scripts were directly extracted, the PDF structure and embedded URLs suggest an attempt to lure users to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 http://kunmobile.vn/files/uploaded/20210903/file/koduwise.pdf In PDF document text
    • https://ms02bet.net/contents/files/3002430570.pdfIn PDF document text
    • http://joyerialaplaza.com/ckfinder/userfiles/files/75430969596.pdfIn PDF document text
    • http://sevenhillsgroup.net/ckfinder/userfiles/files/39323272951.pdfIn PDF document text
    • http://stl-hk.net/userfiles/gisagemewimegekibemafune.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/8nh5qe5d8t2okse0no033dl9s6/firininujarokotap.pdfIn PDF document text
    • https://olgunbey.com/upload/ckfinder/files/gewamexuwepetexopar.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1613a3356452f2---17495949113.pdfIn PDF document text
    • https://millinerandassoc.com/files/file/22739379748.pdfIn PDF document text
    • http://jamalcar.com/userfiles/file/totataxegitiladeku.pdfIn PDF document text
    • http://studiotecnicoforace.eu/userfiles/files/53397375244.pdfIn PDF document text
    • http://gostinica-domodedovo.ru/files/zemitiduso.pdfIn PDF document text
    • http://newbusan.net/FileData/ckfinder/files/20210909_667EEDAE4350418A.pdfIn PDF document text
    • http://jfe.hk/userfiles/76907710507.pdfIn PDF document text
    • http://bckbytow.naszbip.pl/img/upload/files/28244554381.pdfIn PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/31b315f229b654f330e395da6a91a9ed/88084632352.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613d28b4dfea9---varojozamoredowibi.pdfIn PDF document text
    • http://autowassenindex.nl/images/uploads/kabidajobukekobexubururo.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/sqs8o1dk7ucu0jmi7ipqbv2de1/xaxinetazigek.pdfIn PDF document text
    • http://purplebyanki-com.bvirani.com/ckfinder/userfiles/files/tobakenogu.pdfIn PDF document text
    • https://speeddating.lt/speeddating/ckfinder/userfiles/files/xewivakolabemowulilevi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=ultimate+mortal+kombat+3+rom+mamePDF 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_off0000d4b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4B7 19552 bytes
SHA-256: a00d0c60a38ece65fbfc35aca25a2dbb6b86fb578a370f0374b947ee4d31bc2f
font_01_sfnt_off00010723.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10723 10408 bytes
SHA-256: a4333a58f766d691779ef267b514a29d873b363b4f8c431956f83ff7055fcc63
font_02_sfnt_off00011eb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EB5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1