Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8bf2b5eddc0f08e…

MALICIOUS

PDF

84.6 KB Created: 2021-09-18 11:02:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 12c7a0fdc75797fcedee27f57f9a4f7d SHA-1: 592575615c509a420cb1109a0e5929a860e13895 SHA-256: c8bf2b5eddc0f08ee4904ced8bba2f1f328a2eafa3523a811c666e8a459741dc
156 Risk Score

Malware Insights

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

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous embedded URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to phishing or malware distribution sites. The presence of multiple external URI heuristics and a link farm heuristic strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://queure.ru/uplcv?utm_term=use+mobile+phone+as+webcam+android PDF link annotation
    • https://sherwoodchamber.org/ckfinder/userfiles/files/39988186358.pdfIn PDF document text
    • http://bsinteriordesigner.com/userfiles/files/83371408407.pdfIn PDF document text
    • https://dananeye.com/uploads/files/202109040425352972.pdfIn PDF document text
    • http://jiendurancecoaching.com/ckfinder/userfiles/files/83696115523.pdfIn PDF document text
    • http://musicincw.com/fckeditor/userfiles/image/ligigakunizuti.pdfIn PDF document text
    • http://aldobini.it/userfiles/files/josutudefawumel.pdfIn PDF document text
    • https://almudenafernandez.co/ckfinder/userfiles/Files/linajudesarisidesuranowut.pdfIn PDF document text
    • https://fullgame.hu/uploads/files/wibusomafuxovuwufigika.pdfIn PDF document text
    • https://www.pharmawell.eu/ckfinder/userfiles/files/bisefibo.pdfIn PDF document text
    • http://studioturina.com/userfiles/files/95934066830.pdfIn PDF document text
    • http://nage-z.com/ckfinder/userfiles/files/jujimud.pdfIn PDF document text
    • https://ensegun2.com/ckfinder/userfiles/files/junopowelamufovigigefil.pdfIn PDF document text
    • http://iberryhomemade.com/userfiles/files/penunifumawezit.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ee15fc5e0f---turokofunajunezod.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141b695da184---pezibumubavupowe.pdfIn PDF document text
    • http://denki-shonan.com/uploadsfile/bakivit.pdfIn PDF document text
    • http://tyextractor.com/d/files/70057123793.pdfIn PDF document text
    • https://pasarant0g3l-turbo-h1t.com/contents/files/nekoluzelilosuniporis.pdfIn PDF document text
    • http://pi-consulting.ch/download/42334752671.pdfIn PDF document text
    • http://bulgankhangai.mn/userfiles/files/biziwo.pdfIn PDF document text
    • http://xn--3e0b556bhrbowi6undva.com/ckupload/files/kigopomipigixatu.pdfIn PDF document text
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/893b9a546f5cfd820962cc3732ad351d/podunula.pdfIn PDF document text
    • http://audyt.rowerowaszkola.pl/imgturysta/files/meladevesusuvis.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_off0000e48c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE48C 10916 bytes
SHA-256: d4fb3dda77f88ecabd6bd2c0facb1eb10effd8d9dab6169fb81ff731d29a5c50
font_01_sfnt_off0000fd65.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD65 18208 bytes
SHA-256: a787a71f883a87cc9225fb0ebd214bb1dc9ba72b6860f3ed5c784416d97813ef
font_02_sfnt_off00012c6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C6A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1