Malicious PDF — malware analysis report

Static analysis result for SHA-256 77c8e2609d8f4d1b…

MALICIOUS

PDF

64.6 KB Created: 2021-06-23 21:14:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: b28d270492862a2db7a8e64134070626 SHA-1: ed015bb377440f682f03369fc8e35d414ab24ef9 SHA-256: 77c8e2609d8f4d1bc2a8329c5056dafa6e883af7a18b64b7fc037c8c4317b621
156 Risk Score

Malware Insights

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

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 to potentially compromised websites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. While no scripts were explicitly extracted, the nature of the heuristics and the presence of embedded URLs indicate an attempt to exploit users through deceptive content, likely leading to further malware download or credential harvesting.

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 http://hnkingdee.cn/Files/file/202162310758.pdf In PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/f74ad5a6480b3b164262e634be7d9d17/muteritawowaware.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/nizubunosixunoraxalapuken.pdfIn PDF document text
    • http://amexeuro.com/an3_Uploads/file/16754029611.pdfIn PDF document text
    • https://bookatowncar.com/userfiles/file/riwawadifimowekusapowijej.pdfIn PDF document text
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/0f81eb5f1ce26c061ebe50ac98ef5ef3/womaxigimobopinix.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075f6fa9bd62---57526248204.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607da73685f13---pevax.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/8604ade4593e5780d9f86860b02884d3/vafokop.pdfIn PDF document text
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/160726c8189966---39879685149.pdfIn PDF document text
    • https://chaplains-camps.org/upload_picture/file/74942387677.pdfIn PDF document text
    • https://bodwellassociates.com/wp-content/plugins/super-forms/uploads/php/files/3da89c7efb0eef8467930fec251aa287/soradugajamubebone.pdfIn PDF document text
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/cd2bfe5f8ad7b3d9171983924abef0c8/96577726791.pdfIn PDF document text
    • http://voszveszprem.hu/_user/file/91263649142.pdfIn PDF document text
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/zisojukifirupalogade.pdfIn PDF document text
    • http://gustosandvic.com/ckfinder/userfiles/files/fapafim.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/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=carolyn+kisner+therapeutic+exercise+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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bf53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF53 5380 bytes
SHA-256: 46c57254f8e170917f689731e980b13ad45d1ba8b4c1961740c74947f303ef05
font_01_sfnt_off0000d1a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1A3 10420 bytes
SHA-256: f9029634ff0411ced45b0c82744c9035f44fcfcf130b387ea13215048b5d8df1