Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b376b4edede3b8f…

MALICIOUS

PDF

76.4 KB Created: 2021-09-04 22:02:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: cdf1d1aebe9d9bf713a7f5ec2492cd0b SHA-1: 662387b3cf8fbb01f2d46a50f6fa257628ef9289 SHA-256: 3b376b4edede3b8fc960d0c7c540622d88025896fe852751c1198d51c9cf21e2
156 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. It contains numerous embedded URLs, many of which point to compromised CMS upload directories or are structured as a link farm on disposable hosting. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather to host links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://africareview.in/userfiles/file/xodutefexurugitukeja.pdf In PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075e6460677d---98354722425.pdfIn PDF document text
    • http://aimecostruzioni.it/userfiles/files/mivolonegaponi.pdfIn PDF document text
    • https://www.thecandystoresudbury.com/wp-content/plugins/super-forms/uploads/php/files/vsn4gkdn3g1ar0if953a36b2c1/bibod.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/logifelakakivemaj.pdfIn PDF document text
    • https://badoza.net/userfiles/file/14437070907.pdfIn PDF document text
    • http://acpiindia.com/userfiles/file/tonilutevozile.pdfIn PDF document text
    • http://beiwendq.com/userfiles/file/57856439598.pdfIn PDF document text
    • http://www.moyekolodin.com/files/rovunavulutitarofi.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c4ed8a6814---53832100685.pdfIn PDF document text
    • http://rzn-house.ru/upload/file/godetebagatuwa.pdfIn PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/51277438315.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/b9cb918a15210f0b5598c6649bf6f2a2/gisojajuzudasemipiforigab.pdfIn PDF document text
    • http://nsfeed.com/_UploadFile/Images/file/95086114665.pdfIn PDF document text
    • https://akconta.com/uploads/files/purupebedasolino.pdfIn PDF document text
    • https://actor-conseil.com/files/file/12307576804.pdfIn PDF document text
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/f6973a1a65b6386e24ecd49cb89e62c9/dazegodo.pdfIn PDF document text
    • https://www.milestonesmn.org/ckfinder/userfiles/files/7716881842.pdfIn PDF document text
    • https://avvocatoboretti.it/file/46138956755.pdfIn PDF document text
    • http://galsabino.it/userfiles/files/tanozopevefipaguloxovolal.pdfIn PDF document text
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/7ff5a8d81c2f9640b129f7a2d86d31f8/45866683595.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1609a83f715799---zokererewisixez.pdfIn PDF document text
    • http://jjkxmy.com/upload/files/202107190819548273.pdfIn PDF document text
    • http://tensoinox.com/userfiles/files/tinudipikawija.pdfIn PDF document text
    • http://aceonlinementors.com/userfiles/file/nuveviwukaripiv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=milked+by+royalty+pdfPDF 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_off0000c870.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC870 16888 bytes
SHA-256: c9f74d0aa06e1514ed43a654f6abd957b1fe49af9c57ecafd170ae023967788e
font_01_sfnt_off0000f3bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010bd6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BD6 10560 bytes
SHA-256: cbcdce6d82d4c4f5e2e975aadf6bc3b7f23256a41374b87095379b21e3c39717