Malicious PDF — malware analysis report

Static analysis result for SHA-256 085cb405d5d09931…

MALICIOUS

PDF

95.4 KB Created: 2021-09-03 14:52:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: b4f57ce1bb5a54ad611db8ea6799c504 SHA-1: 55f9078c95a760425b3bafe6ca36554eceea1a2c SHA-256: 085cb405d5d099313bc8529d1a4802014a80e90f8cbf871f480db393ffab6e94
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ML classifiers and ClamAV. It contains numerous embedded URLs pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URI heuristics and link farm indicators strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9897

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://nomylo.ru/uplcv?utm_term=angielski+w+t%C5%82umaczeniach+gramatyka+5+pdf+chomikuj PDF link annotation
    • http://xn--80aafmoni2biho.xn--p1ai/admin/ckfinder/userfiles/files/25867234281.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/968c0b7b0aa98541027dd6611209fe22/32304109711.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607095c94a8de---12637424574.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/290747009720.pdfIn PDF document text
    • http://ssanadia.in/userfiles/file/wusexogumejujanas.pdfIn PDF document text
    • https://theatresaucinema.fr/uploads/file/mavopetegisizutidomolux.pdfIn PDF document text
    • https://holcom-wd.holcom.vn/webroot/img/files/zorojomumeb.pdfIn PDF document text
    • http://shosholoza.de/file/57030021475.pdfIn PDF document text
    • https://e-midas.ro/files/file/6757714858.pdfIn PDF document text
    • http://massarentearchitettura.com/userfiles/files/menez.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/5d034d0eb48c75e985fe26461ff15fab/winefojekepesekuv.pdfIn PDF document text
    • https://derey.nl/app/webroot/files/userfiles/files/tumopawaxesaza.pdfIn PDF document text
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/6eku9gg1uau1rdb1kptl9gnvj2/89922192633.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16076031fb692e---46092239646.pdfIn PDF document text
    • https://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/7dc5ea2ab6f597c4f8c3086c492874f2/27273344805.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608327e152681---susunotogil.pdfIn PDF document text
    • https://www.erenang.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608557c048683---95556331608.pdfIn PDF document text
    • http://zentrumok.com/userfile/files/jamifofomipujizid.pdfIn PDF document text
    • http://ooexperience.be/assets/Image/files/xuwefipazigirunefeteloj.pdfIn PDF document text
    • http://caythuocdangian.net/images/files/23052127599.pdfIn PDF document text
    • http://metallpress.ru/files/97632007049.pdfIn PDF document text
    • https://spcinternational.in/ckfinder/userfiles/files/fomexulozelife.pdfIn PDF document text
    • https://embassyinvietnam.com/webroot/img/files/vezimaxuxuxeginekefikom.pdfIn PDF document text
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160f96cb0ac13f---lozolopiwuwerapiwigaxe.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/4rnk2djkstlemnrah361984jfc/lotarezuzinunuratibubo.pdfIn PDF document text
    • https://aprilboya.com/userfiles/file/37882393467.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_off00010c74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C74 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001248b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1248B 11832 bytes
SHA-256: f3d820d2addd0d16c6efb7a1aabae50b7b2d208fa0be023e67591ee7a6a2fbb8
font_02_sfnt_off000140ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x140AD 17424 bytes
SHA-256: 4724e92647dca9435dd931b079df9336c12fffc40f0e45afaa38172134748610