Malicious PDF — malware analysis report

Static analysis result for SHA-256 f9c78b52dc8e6cd7…

MALICIOUS

PDF

69.0 KB Created: 2021-09-26 09:03:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 05499e54e5a900e14d44f9aa6b6560be SHA-1: e4cb4e62dd4159c5ddb9013b7a9ab042340e8458 SHA-256: f9c78b52dc8e6cd79c7af9ad68c734717c7595bd926091ce5581e10856f06cec
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to potentially compromised websites or disposable hosting, indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The primary attack pattern observed is the use of a document as a lure to direct users to external, untrusted resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://oniceh.ru/uplcv?utm_term=english+comprehension+exercise+pdf PDF link annotation
    • http://csp.hu/editor_up/wilezodexemobopaxobakase.pdfIn PDF document text
    • http://daejonggyoyc.com/userfiles/file/20210906144327.pdfIn PDF document text
    • http://saharun.org/uploads/ckfinder/userfiles/files/xomudekesofuweve.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16141ac08b1d3a---86188166056.pdfIn PDF document text
    • http://iehyun.com/editorupload/file/96956143290.pdfIn PDF document text
    • http://perevodvnegiloifond.ru/pict/file/86313319125.pdfIn PDF document text
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/cc7tr6h6uhqbimtbk9r2vrff95/37599641924.pdfIn PDF document text
    • http://www.contal-farmer.com/uploads/files/67466994620.pdfIn PDF document text
    • http://meubelenindex.nl/images/uploads/sufezikavig.pdfIn PDF document text
    • http://dmkert.hu/files/file/26654804631.pdfIn PDF document text
    • https://aluminiosarla.com/userfiles_arla/files/6655385792.pdfIn PDF document text
    • http://tienhasteel.com/app/webroot/upload/files/tozukavo.pdfIn PDF document text
    • http://cesnek-vysocina.cz/UserFiles/File/106140567.pdfIn PDF document text
    • http://musicfriend.vn/public/default/ckeditor/files/wopujefunidiwir.pdfIn PDF document text
    • https://rijst.nu/userfiles/file/21659810749.pdfIn PDF document text
    • http://kodemari.info/data/files/betix.pdfIn PDF document text
    • http://superfishinglewood.com/uploads/files/20988160012.pdfIn PDF document text
    • http://t-eamplus.de/web/editor/files/16393341277.pdfIn PDF document text
    • http://swhwsolution.it/ckeditor-ckfinder-integration/uploads/files/5625378027.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/161462a99a1742---54852430730.pdfIn PDF document text
    • http://alacarte-design.de/userfiles/file/7724652520.pdfIn PDF document text
    • http://www.galiantsolutions.com/emailimages/file/pozutanizedijofodum.pdfIn PDF document text
    • http://xn----dtbhwhggdaoqfh3d.xn--p1ai/media/file/6422796423.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_off0000afbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFBF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c7d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7D1 15496 bytes
SHA-256: 7c925442119f4b5dc2625dc60f559c7e4432883549875872043eded3d9cc75bb
font_02_sfnt_off0000eda2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDA2 10892 bytes
SHA-256: 2102bb9354aeb538a91225ebd16035903d0c632bcb21e73f4db3c40b7223b886