Malicious PDF — malware analysis report

Static analysis result for SHA-256 73fb3cb58ebce932…

MALICIOUS

PDF

92.8 KB Created: 2021-06-01 15:28:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 201f8bc5d038ad0a985edcba937c5508 SHA-1: 08674ce68f06c86db28db32ad6f2924835481ae4 SHA-256: 73fb3cb58ebce932199a386c502d0929a00fe0dfac931ebb3642947f3181f8ca
186 Risk Score

Malware Insights

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

The file is a PDF that contains a large number of external links, many pointing to disposable domains or potentially malicious URLs, indicating a link farm or phishing attempt. The ClamAV detection and ML classifier strongly suggest malicious intent, likely to redirect users to malicious sites or for SEO spam. No scripts were extracted, but the PDF structure itself is used to facilitate the malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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 https://laborke.ru/pbw?utm_term=heavy+is+dead+bendy PDF link annotation
    • https://kowulenube.weebly.com/uploads/1/3/2/7/132740682/rowano_gizowup.pdfIn PDF document text
    • https://zedebofewel.weebly.com/uploads/1/3/4/5/134594015/romigej_logatexukefiva.pdfIn PDF document text
    • https://fevobubutexub.weebly.com/uploads/1/3/4/4/134481878/niwojagororonave.pdfIn PDF document text
    • https://pegepigav.weebly.com/uploads/1/3/4/4/134481067/jixadikagos.pdfIn PDF document text
    • https://siropenisawad.weebly.com/uploads/1/3/4/3/134353493/xufosuxotew.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4379970/normal_5ff70d36b5c94.pdfIn PDF document text
    • https://bejixetixozivi.weebly.com/uploads/1/3/4/4/134499198/kalat_xanojosob_pezaxanajivebu_rekobexigozuni.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369920/normal_600df259b5514.pdfIn PDF document text
    • https://merasezimimuzal.weebly.com/uploads/1/3/7/5/137510453/752c81ca76ce64.pdfIn PDF document text
    • https://xizotikozuza.weebly.com/uploads/1/3/4/5/134587863/5160091.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/1b4e5fb7-700b-43d0-af92-7fe0ee66ca27/exercice_mole_seconde_avec_corrig.pdfIn PDF document text
    • http://mizunebapod.pbworks.com/f/fegometowebatezatakop.pdfIn PDF document text
    • http://vatojorisa.pbworks.com/w/file/fetch/144444990/87294134097.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fa59cec6-a1ba-4315-a88b-123624d7a708/what_happens_in_after_we_collided_book.pdfIn PDF document text
    • http://jesababa.pbworks.com/f/how_to_adjust_husqvarna_zero_turn_steering.pdfIn PDF document text
    • http://gatasulupu.pbworks.com/f/47925387742.pdfIn PDF document text
    • http://tebejeloxid.pbworks.com/f/how_to_treat_a_sick_green_cheek_conure.pdfIn PDF document text
    • http://vugufosenene.pbworks.com/w/file/fetch/144446397/turbo_downpipe_size_calculator.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5cdbedc6-5441-4a04-9cbe-82b2588aedf3/22656128402.pdfIn PDF document text
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011e72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E72 3884 bytes
SHA-256: de1ad3a3a640826959818e873b2746a24b8da9ba0dbeb19717d9374298452cfe
font_01_sfnt_off00012c38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C38 4956 bytes
SHA-256: 2cfa0e0c4e2753349de44c328641dfd2229efbd9dec253ebb07ad6c3eb9e33fa
font_02_sfnt_off00013d29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D29 12112 bytes
SHA-256: 95c6acfa70f9540ea733d0fd982500728c7540ad2c951b2c51af09cbcc4eeeaa