Malicious PDF — malware analysis report

Static analysis result for SHA-256 71bb0dc4e51c0409…

MALICIOUS

PDF

75.2 KB Created: 2021-10-08 23:29:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 052e5416d0d5a8044a1ada7fbe31741e SHA-1: b857905c79c86c19c86d3d912a7e3ddcf038cd33 SHA-256: 71bb0dc4e51c0409b0a225cb9e885a0c8daaf2a611ce8f1d9814f7138e7e8796
126 Risk Score

Malware Insights

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

The file was detected by ClamAV as 'Pdf.Phishing.Trojan' and flagged by an ML classifier with high confidence. It contains numerous embedded URLs, many of which point to PDF files on various domains, suggesting a link farm or redirection mechanism. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further indicates a malicious intent to distribute content via disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://arredamentoambienti.it/img/file/43664311171.pdf In PDF document text
    • https://rh-h1tapi-turbo.com/contents/files/vaxugowube.pdfIn PDF document text
    • http://yokosohk.com/files/fckfiles/file/43059246073.pdfIn PDF document text
    • https://rosebankprimary.co.za/inc/ckfinder/userfiles/files/23225338195.pdfIn PDF document text
    • http://synhbio.com/upload/files/68361688675.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/850269167a97845fad4b7d79300b2354/keramiwe.pdfIn PDF document text
    • https://officialbacknumber.com/editor_up/vakidubosavivanoman.pdfIn PDF document text
    • https://dnsbp.com/all4help/fckuserfiles/file/4321624414.pdfIn PDF document text
    • http://tourbusan.net/FileData/ckfinder/files/20210920_E1E466091F3D940C.pdfIn PDF document text
    • http://biogenetec.tw/image/files/20210919_223458.pdfIn PDF document text
    • https://irrisyst.eu/files/file/44556457223.pdfIn PDF document text
    • http://greenld.com/userfiles/susolagozijupomipoka.pdfIn PDF document text
    • http://studioscoponi.eu/userfiles/files/34103549178.pdfIn PDF document text
    • http://luligang.com/ckfinder/userfiles/files/dumubejofofodube.pdfIn PDF document text
    • http://tractortools.cz/ckfinder/userfiles/files/bodojufuri.pdfIn PDF document text
    • https://brazilairporttransfers.com/ckfinder/userfiles/files/84039926799.pdfIn PDF document text
    • https://pasationtravellers.com/root/FCKeditor/file/90780442568.pdfIn PDF document text
    • http://lobi.md/userfiles/file/92666638526.pdfIn PDF document text
    • https://www.scmsgroup.org/ckfinder/userfiles/files/donojikarozerutisow.pdfIn PDF document text
    • http://nincity.de/inline/file/xerenajokuzigujodesud.pdfIn PDF document text
    • http://www.fd.ntou.edu.tw/ckfinder/userfiles/files/1772101960.pdfIn PDF document text
    • https://xn--dokumaanahtarlk-llc.net/userfiles/file/48845750459.pdfIn PDF document text
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/161526a55d1ccb---kajovazosopoxul.pdfIn PDF document text
    • https://peltonfell.org.uk/ckfinder/userfiles/files/32777585185.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=haccp+plan+for+fishPDF 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_off0000c3c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3C0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dbd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBD2 17164 bytes
SHA-256: f0b6822f6cfad2853262e5612584837a27543ff10dcd9fe55c281eeba6f60ede
font_02_sfnt_off00010810.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10810 10340 bytes
SHA-256: a534ad3e0fb95c003422d7172352b54899a221682111dd682b115ca995ab89fa