Malicious PDF — malware analysis report

Static analysis result for SHA-256 18f491118d41a749…

MALICIOUS

PDF

75.6 KB Created: 2021-04-28 09:43:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 85632ba955b29d3a3a3f8018cd483bf6 SHA-1: 5066d285cb5bb9c52eeed1642658a09ef2181449 SHA-256: 18f491118d41a749f6ef5dc628001b6e4b97e25874b1a400156c2fdf18eeebc7
136 Risk Score

Malware Insights

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

This PDF document is designed to trick users into downloading a secondary malicious PDF by presenting a fake executive summary. The document contains numerous links to compromised WordPress sites, many of which host further PDF payloads. The ML classifier strongly indicates maliciousness, and the presence of multiple PDF_RANDOM_URL_LINK and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics confirms the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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 https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/vpgip5u6ljd0a0mrmaudo867s0/29469662736.pdf In PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/16075a306a9912---puluwubogezifuxuxu.pdfIn PDF document text
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/4bd270a734c1243566bde6a9a6783e4a/17985059992.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/fb4d8823265ce13d160213c5c2201531/kedunenevogemu.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160748fc5b1e2d---barewofun.pdfIn PDF document text
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/814h3imic18dnu4o0krbt59tb7/42362639858.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608357fe0ae24---gipebokoxatovezetor.pdfIn PDF document text
    • https://caravanandre.it/wp-content/plugins/super-forms/uploads/php/files/35887f9e478cf8ad6920330526a2336b/sazosugi.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/160726513b2c7b---relelubuname.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9301a72cd---83549216335.pdfIn PDF document text
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/21304jgvj3fl5etb7ecm1r3i37/65989850012.pdfIn PDF document text
    • https://mission4recruitment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088473077628---72203283450.pdfIn PDF document text
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/3keusn2qr0istu3k6irht9fp8v/83918205630.pdfIn PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/2b00762eb4e4c14307374df428242fb4/norofikulerajetijugemufa.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/~3/1xuhb7AK25c/uplcv?utm_term=executive+summary+of+a+marketing+reportPDF 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_off0000eac0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAC0 5556 bytes
SHA-256: 2a53d6135d5db92f88ea344bdde2057c59ad7743a16e60c3cfe7f394ed416b55
font_01_sfnt_off0000fdac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDAC 10408 bytes
SHA-256: 75e98d0013aa7224255dafa03a5a65f70d2e80fbca20b407fedcbf6db735d03d