Malicious PDF — malware analysis report

Static analysis result for SHA-256 16cb61ab79684c63…

MALICIOUS

PDF

71.2 KB Created: 2021-09-05 03:15:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: cdd4ec0447b6a760314b7b1c14c514dd SHA-1: fd2ab6b5f2c2d4a372039b97d6abe1ebab246bea SHA-256: 16cb61ab79684c6306c5212eb7b05f2f10dc96f4056015c551169070638b7ba1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a phishing or malware distribution campaign. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics indicates a deliberate attempt to create a link farm for malicious purposes. No scripts were extracted, but the overall structure and heuristics point to a malicious document designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://crewmak.ru/uplcv?utm_term=uti+pan+correction+form+pdf+new PDF link annotation
    • http://prospekt-rostov.ru/ckfinder/userfiles/files/71044381252.pdfIn PDF document text
    • http://pathtojanna.com/userfiles/files/41436210504.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/79669726623.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/0b24b74122f5825f6df8873c0116b74e/fusanejar.pdfIn PDF document text
    • https://motoquadro.de/userfiles/file/kabavavojijoniwi.pdfIn PDF document text
    • https://bleikss.com/userfiles/file/suzivexagirup.pdfIn PDF document text
    • https://essaidafm.com/uploads/FCK_files/file/visedaner.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16131f80b9de85---40746917204.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160839ffd3f90f---torisazigelimogakiv.pdfIn PDF document text
    • http://parkwaywest1974.com/clients/861606/File/88090305890.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/9af84b299e82159ad7977c4a196d301e/71404429661.pdfIn PDF document text
    • https://mastirz.com/userfiles/files/lumit.pdfIn PDF document text
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ae84116604b---87311955086.pdfIn PDF document text
    • https://starfoil-mail.nl/uploads/wysiwyg/41802214910.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160aa3fd7bff9a---94266872624.pdfIn PDF document text
    • https://avenue102.com/uploads/file/15706646058.pdfIn PDF document text
    • https://hawkseyetravels.com/assets/ckfinder/userfiles/files/vivalisifud.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160709907a08c4---1655708722.pdfIn PDF document text
    • https://telorgabus.com/contents//files/49823821682.pdfIn PDF document text
    • http://felixefontesadvogados.com.br/ckfinder/userfiles/files/tixojapaxekanerivon.pdfIn PDF document text
    • http://esenkardeslerinsaat.com/resimlerfiles/sategikuvoveto.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/49251761262.pdfIn PDF document text
    • http://harrisonsfamilyreunion.com/clients/62911/File/dunizaxesogolew.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_off0000b3a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3A1 16896 bytes
SHA-256: ffa31681c58da24d8632e758ed398fbdf36a97e4bf4141fae3361c53b67c6b8d
font_01_sfnt_off0000deca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDECA 10660 bytes
SHA-256: 0baf2006f5a30818223d2cd2aa645932f388ebd634d5c9b76925aed672274f1a
font_02_sfnt_off0000f746.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF746 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.