Malicious PDF — malware analysis report

Static analysis result for SHA-256 c7b7736c458c4b4c…

MALICIOUS

PDF

76.2 KB Created: 2021-06-11 12:23:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: a34c03bcec677ec076a24794cba10ca8 SHA-1: 3b7769ff6fabb5dcaed1bac688f72fb11e4e997e SHA-256: c7b7736c458c4b4c5c405015fc5e01de8fbe705be2705a4d89f3baeb25bb1b88
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The document contains numerous embedded URLs pointing to compromised websites and disposable hosting, suggesting it functions as a link farm for phishing or malware distribution. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://krisoc.ru/uplcv?utm_term=an+introduction+to+thermal+physics+solutions PDF link annotation
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/3e73ed24e870321c3cf5f3e5cfeb250a/fufevo.pdfIn PDF document text
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/8f5113f1716816d70ad72998e7f8290c/siripixinegetovetigadofux.pdfIn PDF document text
    • http://curry-box-deluxe.de/userfiles/file/lazorajofonudabur.pdfIn PDF document text
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/mgeoi2n8qhe5gop4b8vp8g2m38/lexeganolegitejugasuke.pdfIn PDF document text
    • http://www.radiooro.com.mx/media/images/uploads/files/70444638163.pdfIn PDF document text
    • https://balance-global.com/wp-content/plugins/super-forms/uploads/php/files/l4bt1nfijaosle6llqnh3e767t/86007082797.pdfIn PDF document text
    • https://collegemahan.ir/basefile/collegemahanir/files/14339074307.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/485468d140eb66e5ec8e00519d1394fd/21954406530.pdfIn PDF document text
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/topqebg45g4feg3n2dfg0deo74/98527648932.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/faaf445ccc065c8de0c869f8d67618f7/89515433095.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/0db8afb3b4d441a8aa2bd4304d27f91e/tumalilisusakedidanuz.pdfIn PDF document text
    • http://studiogiovannone.com/userfiles/files/puxugemoj.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/ivbh1tdgfl33pl9btvqh7q4hf1/35603976177.pdfIn PDF document text
    • https://centrosteadycam.it/wp-content/plugins/super-forms/uploads/php/files/a648b1e27a9b7976fda727a4f0b9c92f/49213505011.pdfIn PDF document text
    • http://www.doctor-carpet.com/wp-content/plugins/super-forms/uploads/php/files/g62t0gaa50si9u46bt5nusla32/58744720581.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607fb08214755---zudedazesojasoliru.pdfIn PDF document text
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a5a415dd063---2436515129.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ea93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA93 5404 bytes
SHA-256: 3417f014a446597fd745d54778aae606da3cebc07fefeadf87420ea951046ac9
font_01_sfnt_off0000fccc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCCC 11264 bytes
SHA-256: e39e2bbdb1d089cc7b26c065eeaa046d9b5e10289c4988b71b5edc4118c26197