Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b79ef32148c6865…

MALICIOUS

PDF

76.5 KB Created: 2021-10-10 21:45:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 904bf15f630ed465f6f37cc156e1a14d SHA-1: 45a659981bbbf0a89886bbcd8dabae376c4a9ae1 SHA-256: 9b79ef32148c6865e9e1fb63227e062140c1b315f88910087dc699846e6a7ef4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which point to compromised CMS upload storage and are structured as a link farm on disposable hosting. The document body is unreadable binary data, suggesting it's not meant for direct user consumption but rather to host links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/bb461185c35e8853adb0324dcc698789/53663040193.pdf In PDF document text
    • https://www.dogandemir.av.tr/paketler/ckfinder/dosyalar/files/59818884025.pdfIn PDF document text
    • https://globalcareerclub.com/FCKeditor/userfiles/file/56779729705.pdfIn PDF document text
    • http://recit-de-vie.fr/userfiles/file/18203562539.pdfIn PDF document text
    • http://etcpremium.com/userfiles/files/26212969030.pdfIn PDF document text
    • http://dxczx.com/ckfinder/userfiles/files/20211008_050752.pdfIn PDF document text
    • http://finproekt-msk.ru/userfiles/file/waxifinijakodidif.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/5a4cc9eb2df2e8fa39f66447bcf0a8fc/mefonateromilirotodasupi.pdfIn PDF document text
    • https://waxparadise.pl/userfiles/file/buriwiwijagibixogi.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/8340338008.pdfIn PDF document text
    • http://xn--franzsischebulldoggen-lec.eu/userfiles/file/beruvusexumejivu.pdfIn PDF document text
    • http://strelnicebudejovice.cz/userfiles/file/41829053614.pdfIn PDF document text
    • http://oxigensupplies.com/shipinc/userfiles/files/fegunaribatusor.pdfIn PDF document text
    • https://afra24.com/basefile/afra24/files/nuvulevuveredejewaxawa.pdfIn PDF document text
    • http://heizler.hu/files/file/foseribom.pdfIn PDF document text
    • http://santabruna.cl/upload/file/43954199398.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161318db8c16b0---14602361638.pdfIn PDF document text
    • https://pcetravel.com/files/file/gizer.pdfIn PDF document text
    • https://xn--i1aam8cb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9b63c21c6e088e74059a0837d2f1abe2/zutesipamifuza.pdfIn PDF document text
    • http://zgic.ru/!upload/files/97361832605.pdfIn PDF document text
    • http://autoescuelatosal.com/galeria/files/42984710166.pdfIn PDF document text
    • http://methese.com/upload/files/kitavajuba.pdfIn PDF document text
    • http://circolonauticofavignana.it/userfiles/files/63966560588.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=be+past+continuousPDF 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_off0000c94a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC94A 10372 bytes
SHA-256: 63380610fade716a39cc15cae399b62f29f13f25a98ec19ec55c4f122c516e8c
font_01_sfnt_off0000e0ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0EF 16996 bytes
SHA-256: 31b31f3064848ca114501ff6bf0f11668443c012cbb5968ee8a889119e19fde8
font_02_sfnt_off00010c4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C4A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1