Malicious PDF — malware analysis report

Static analysis result for SHA-256 78f3f563207c5f82…

MALICIOUS

PDF

88.9 KB Created: 2021-08-23 19:00:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: 87f85cd4fec7d1709f11b859a0620559 SHA-1: 514cc015005f11c02b724fc638f9709b21aa7214 SHA-256: 78f3f563207c5f8220d517fec2d522f87107946b1bf74fc744dc2a0e5622573f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by a machine learning classifier as malicious and contains heuristics indicating it is a link farm pointing to compromised CMS uploads. The critical heuristic 'SE_SECRET_RECOVERY_LURE' strongly suggests the document's intent is to trick users into providing recovery secrets or private keys. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of a phishing or social engineering attack, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 6

  • Recovery secret / private key request critical SE_SECRET_RECOVERY_LURE
    Document requests recovery phrases, private keys, backup codes, or saved passwords. Requests for these secrets in a document are high-risk.
  • 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://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c7e0d68329---73319050278.pdf In PDF document text
    • http://unseenadventure.com/userfiles/file/6791882035.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160e8b14b2b90a---kenalipux.pdfIn PDF document text
    • http://93564497.com/userfiles/moruvu.pdfIn PDF document text
    • http://www.hussco-steel.com/husscofiles/files/8851761371.pdfIn PDF document text
    • http://tpdw.pl/userfiles/file/75051318200.pdfIn PDF document text
    • https://daiichigroup.net/uploads/news_file/davumedufafaxo.pdfIn PDF document text
    • https://protradingindia.net/userfiles/file/povaxobuzeremaramusasul.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/6222792053.pdfIn PDF document text
    • https://baxsporthorses.nl/userfiles/file/juporagaza.pdfIn PDF document text
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084d07c1fabe---31521761036.pdfIn PDF document text
    • http://dbjhockeytournament.com/clients/f/f9/f9ff496842c877cbb4522510b668f2a2/File/88605003956.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1608d218a4b152---94472752142.pdfIn PDF document text
    • http://www.circoloaletrium.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608e8275530d4---43235646209.pdfIn PDF document text
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/n91prfsnjuvn4dqj03ig1e2mu5/42524598032.pdfIn PDF document text
    • http://tavio.su/files/file/86456241332.pdfIn PDF document text
    • https://kaptenhoki.net/contents//files/51716804618.pdfIn PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/161188220dc7fe---16625201401.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607aae2810f10---makobutir.pdfIn PDF document text
    • http://circuitvietnamcambodge.com/hinhanh/file/77861860616.pdfIn PDF document text
    • http://polishingmarblefloor.it/userfiles/files/sewalofonunu.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/beace33c4b6b79fdfd53c0a8cf19a081/lexejapevok.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bda7226fde7---91943698820.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=gallagher+6000+controller+manualPDF 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_off0000f758.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF758 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010f6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F6A 17032 bytes
SHA-256: 74fe641d2e659600388011042c7aba484c82549b820eca076c63a0382106ff67
font_02_sfnt_off00013c1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C1E 10844 bytes
SHA-256: cadfe85849a25df7e605282dad16ec6424e080615626a869b679549136da2c18