Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9203c5bf04d7992…

MALICIOUS

PDF

88.0 KB Created: 2021-07-19 13:55:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 478216e02402201e177b7cbafb1312da SHA-1: b91aafb2495cdac961503246660507aaf75a914d SHA-256: a9203c5bf04d79921106c191b3f048f6bf35ff2a4d8f53e21e247d63ed1518fb
156 Risk Score

Malware Insights

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

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The PDF's structure and the presence of external links are consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://aimtronu.org/userfiles/file/bitajibasulifux.pdf In PDF document text
    • http://gayaarchi.com/userfiles/file/20210521010913.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/160dd87bc50674---7613501018.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/fbb48dfca7e97251f73ba41ea9b5ec6d/dapakidimokuvu.pdfIn PDF document text
    • http://argyler.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074a73298f75---52890860159.pdfIn PDF document text
    • http://chargers68-50th.com/clients/3/3d/3dd154274af4887fbe356f6dcfc18689/File/64876858407.pdfIn PDF document text
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/aamktlhdsvvfb7kb7lkg8tb6m7/nitulazolaravigulagon.pdfIn PDF document text
    • http://www.niziointerior.pl/upload/file/dukosanudelajuwajogixigon.pdfIn PDF document text
    • http://solarhomepage.ch/fckeditor/editor/images/file/57696675503.pdfIn PDF document text
    • https://serviceservice.eu/userfiles/file/80708283662.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160737425b905b---77772120706.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/16091ba953268b---futexav.pdfIn PDF document text
    • https://haps.company/wp-content/plugins/super-forms/uploads/php/files/nc465cfan9eeja6k4a8dd5sk05/49570324923.pdfIn PDF document text
    • https://baohohoanglong.com/userfiles/file/goliwixinesidetoti.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/6c0af13662e6780a72f67c60edd91a57/18082906936.pdfIn PDF document text
    • https://humicdp.com/uploads/2021-07-08/images/files/50682730731.pdfIn PDF document text
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/9771be4ceffd85962270dcd6c5a62700/65941082867.pdfIn PDF document text
    • http://epoetryworld.com/clients/53741/File/66012147074.pdfIn PDF document text
    • https://flexrocksrollovers.com/wp-content/plugins/super-forms/uploads/php/files/evqbgukgospkjo920c3ipq3gfa/45407485672.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607380f662ebe---77468918096.pdfIn PDF document text
    • http://airsoft1.ro/files/file/wekemexe.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/odp66trjnjjkuiu82864v8nn9d/50269339333.pdfIn PDF document text
    • https://www.uniqueartzz.com/wp-content/plugins/super-forms/uploads/php/files/e64r51ea8gfmul98hh0foh02dt/zuvamolozoma.pdfIn PDF document text
    • http://theheavent.com/userfiles/files/54422515349.pdfIn PDF document text
    • http://asupuro.com/user_data/image//file/povupujajurawogub.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=master+your+thoughts+master+your+life+free+pdfPDF 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_off0000f594.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF594 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010dab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DAB 11048 bytes
SHA-256: 117c6e8c653b7b3234be8a8551d11b63f5bc497bbe20392bf0e0b52b566c0d53
font_02_sfnt_off00012735.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12735 16528 bytes
SHA-256: 63b57b3929dae5dbe6747dee78a9f92e42a67e0a483e5249aaa1ad2f0afaf3e0