Malicious PDF — malware analysis report

Static analysis result for SHA-256 3817c6dd9a3aff6b…

MALICIOUS

PDF

85.7 KB Created: 2021-09-02 07:09:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: d744cb085badb9dbfb9c9959b3a70b14 SHA-1: 698994a5ba3475c5a945985888f7e810d3ba5818 SHA-256: 3817c6dd9a3aff6b340a50fffb734f073558ff7a40def06e796f1276f3b0978c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm hosted on multiple compromised websites, directing users to download a 'terraria game launcher'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely a phishing or malware distribution lure. The presence of numerous links on compromised CMS upload storage suggests an attempt to obscure the true origin of the malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9919

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://studiolaviano.it/userfiles/files/68106239817.pdf In PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/161147c909318b---36520270155.pdfIn PDF document text
    • http://sistersaviopublicschool.com/userfiles/file/88274713834.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/f4946a785687a95fce1d146b7fa0a822/99901087982.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7a620096ae---70907651733.pdfIn PDF document text
    • http://universalthailand.com/images/uploads/ckfinder/files/73644877368.pdfIn PDF document text
    • https://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/551261099071c030c3eba9d4affe2efa/1063818884.pdfIn PDF document text
    • http://sjatupornservices.com/file_media/file_image/file/23461783827.pdfIn PDF document text
    • https://mma-montessori.com/admin/ckfinder/userfiles/files/garadupuxuridazida.pdfIn PDF document text
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/l3ls5do73bq508cj7glvq4mlh5/62766155176.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b83b6e35e15---modofujowaxolez.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/5b8ff27df557c15cc57dd065287421b1/gaxofukok.pdfIn PDF document text
    • http://chinalanpa.com/images/upload/File/kusetivowumarufaneze.pdfIn PDF document text
    • http://sl-light.ru/design/img/upload/file/mobumutetilulimorusizur.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/160782fac54fd5---suwabaxi.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ad28ac7df5---nilofobusumuve.pdfIn PDF document text
    • http://findusafranchise.com/files/files/97180693756.pdfIn PDF document text
    • http://pspectr.ru/userfiles/file/ninaxonuwenugaga.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/b2f16bf502ae1d5cb8d0f3fadda39466/65102748991.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/kibukuzoki.pdfIn PDF document text
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/06b890241af53e590340b94105eee4ea/rofipagigudofuvujipo.pdfIn PDF document text
    • https://www.engltg.com/wp-content/plugins/super-forms/uploads/php/files/cf7671f18eebd0d43d8aebe2ade5293d/90130823748.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ec9ecc8dae9---76178139633.pdfIn PDF document text
    • http://didocrosby.com/imagenes/file/vabomibukedekus.pdfIn PDF document text
    • http://fixafilm.se/userfiles/file/71907268984.pdfIn PDF document text
    • http://eksan-ltd.com/userfiles/file/82952240228.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=terraria+game+launcher+downloadPDF 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_off0000ea04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA04 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010216.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10216 18068 bytes
SHA-256: 6234264b7a548c81d3d947956eddb5b141eac10999e516351094da32dedbc1ca
font_02_sfnt_off00012ff4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FF4 10700 bytes
SHA-256: a0af494c94b43fc4a19f36c5f1f844610590c6053c9b44db1e779ea2e2609375