Malicious PDF — malware analysis report

Static analysis result for SHA-256 24551c4146510be7…

MALICIOUS

PDF

72.9 KB Created: 2021-05-21 20:34:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 48a0930cc04762d9dae8f7dda1fe1c79 SHA-1: 99d87d28e7df9e342229ec74c4876ca64ec1d910 SHA-256: 24551c4146510be7f4e29222aed093c449a5b6a62370f9a5c5423656c124aff9
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains numerous links pointing to compromised WordPress sites, likely serving as a link farm to distribute further malicious content. The presence of these links suggests an attempt to direct users to malicious PDFs hosted on these compromised domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607c55c3c206d---29808362636.pdf In PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609ece946e211---zepupopenokatag.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a7b7bc48809---50747105119.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e74de9a981---kilejoravaf.pdfIn PDF document text
    • https://refour.dk/wp-content/plugins/super-forms/uploads/php/files/379d7c6318e793c13c34a0083efd6fe4/jutusez.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092d6835a2cb---71796421630.pdfIn PDF document text
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608217b4993c2---vidugizir.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607b96452bfde---ruwaropaparamaso.pdfIn PDF document text
    • https://tavio.ru/files/file/gaboxuver.pdfIn PDF document text
    • https://anmoul.com/userfiles/file/medot.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cc76c35cab---74407565806.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/4e11e0d5c0ba47588e4fa328e7a6853c/wetowovujoxebububup.pdfIn PDF document text
    • http://w-f-l.de/user_img/file/mafamewakenifom.pdfIn PDF document text
    • http://boursemoi.com/userfiles/file/33099655903.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/3cb77d665c92469677d62977b970ecca/30127358697.pdfIn PDF document text
    • http://terapeutickemasaze.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1606f252798542---nuxepasinovofas.pdfIn PDF document text
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/4ac604726be613a1cc4ff91f97b97dbd/30272350080.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=how+to+describe+happiness+in+a+poemPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e161.bin
8145f6d7aaca68f37bbd4519e54fb85e85df6d169185b3d44ab845b60010c27d
pdf-font-stream PDF embedded font (sfnt) at offset 0xE161 5476 bytes
font_01_sfnt_off0000f3e1.bin
34dd5167303de3a8d76f9bcc7f5aeeee0bad46a17b56cd38f86ab94d7073c7da
pdf-font-stream PDF embedded font (sfnt) at offset 0xF3E1 11140 bytes