Malicious PDF — malware analysis report

Static analysis result for SHA-256 a83e44f2b337d8ab…

MALICIOUS

PDF

77.5 KB Created: 2021-03-11 09:42:03 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 04583a14f18bda7cdcb1d5756a1403ad SHA-1: 96bea1da1669819e17cb857ef1bd36699022406d SHA-256: a83e44f2b337d8ab2c40bf6e872d32f4490fc9974b1253573a55e169b586fe42
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

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
  • 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://xajibur.ru/wb?keyword=battletech%20game%20mech%20spreadsheet PDF link annotation
    • https://cdn.sqhk.co/bujerinalo/Cjjhvjh/skull_game_arcade_games.pdfIn PDF document text
    • http://nesakud.mypressonline.com/1994_yamaha_timberwolf_250_carburetor_rebuild.pdfIn PDF document text
    • https://cdn.sqhk.co/vodadavubex/igjIhaS/90927201586.pdfIn PDF document text
    • https://cdn.sqhk.co/raxedaninaso/ibWYh4u/58599558659.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://piwakitidi.onlinewebshop.net/puwobum.pdfIn PDF document text
    • https://88749095-6fd7-453f-8e8a-15b48fe47dd1.filesusr.com/ugd/e4d7df_7523d61b9d5d40f1a007e34c2584ca36.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/3b03c8f9-de4a-4bec-9b26-0903f47c0711/how_do_you_renew_your_drivers_license_during_covid-19.pdfIn PDF document text
    • https://a815f367-2516-4b88-9496-eed07d5c1eb7.filesusr.com/ugd/665c20_824ace9b30e54ff991fb5576620828b2.pdf?index=trueIn PDF document text
    • https://09ec9d85-9312-4337-94d0-b84080e05f2e.filesusr.com/ugd/ac0094_bb7047a6b1e242a8a7f614cec5d017a7.pdf?index=trueIn PDF document text
    • https://4779f2f8-a33e-4327-9c78-21ee0bcf4620.filesusr.com/ugd/31bf02_4d89c94512eb4acb8beb830b0eefcbf1.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/bb0b63a4-1b4a-41c4-8c64-b65cb485b932/2013_jeep_grand_cherokee_overland_hid_bulb_replacement.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e32bfebd-06f5-4b8a-ac12-8d6a9acecd15/rheem_pronto_tankless_water_heater_service_manual.pdfIn PDF document text
    • https://26bfc7ce-baa4-43a1-9280-72312523cbd3.filesusr.com/ugd/5af86b_ceff5c11378d4ace9eda31c3ed935f12.pdf?index=trueIn PDF document text
    • https://662517ce-f374-4037-aebd-99b1dbe00103.filesusr.com/ugd/0c4177_bcb851d7844d450299dca4f34f0826b9.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/b7dc1250-0eca-4233-97de-e1391b4e2f7e/mepoxemopako.pdfIn PDF document text
    • https://7e70056c-c2aa-4e53-98c5-50750123c107.filesusr.com/ugd/f8ae5d_25aae66d9f244bdbb31d5d9e20cd3fdf.pdf?index=trueIn PDF document text
    • https://01c19f78-c7d0-441a-b56a-8672493f87de.filesusr.com/ugd/9d66c7_0e223b27a1e543069ad6304125eb10ac.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/7fb6c260-31a9-49d3-a025-290137ac0593/17816413748.pdfIn PDF document text
    • https://d497f082-4895-42de-a72c-038d9367c8a3.filesusr.com/ugd/8e727b_dd1a073825d449bf9807d15e96842d1b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/6d0bac4f-fb0c-4e68-8164-689afc4b00af/33294843992.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000efa1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFA1 5536 bytes
SHA-256: 9b05c6e380c343b92775b66f88163048d09da1b7641f407b563f75da79772bba
font_01_sfnt_off00010244.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10244 10648 bytes
SHA-256: c8a78a9bd049259f1f5d5377612c372f23b5dac954a0617e77fd567f2eb95a6b