Malicious PDF — malware analysis report

Static analysis result for SHA-256 83dbad7bdb5ee655…

MALICIOUS

PDF

72.1 KB Created: 2021-04-27 23:41:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: c05cad1179f609d2f616d09a2a81d3b1 SHA-1: 221c30b6ef6edb2a88cfd44ad9dc3c8bc206fac5 SHA-256: 83dbad7bdb5ee655007ed1862af5cd84471ca1e3bb3cbfc4a035b73759142fc7
186 Risk Score

Malware Insights

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

This PDF file exhibits characteristics of a link farm, with numerous embedded URLs pointing to external resources. The primary URL, 'https://leonvi.ru/strik?utm_term=brother+7860dw+toner+reset', suggests a lure related to printer toner, while other URLs indicate a broader link farm strategy. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://leonvi.ru/strik?utm_term=brother+7860dw+toner+reset PDF link annotation
    • https://cdn.sqhk.co/tajiwikiter/ihThhgd/14746359436.pdfIn PDF document text
    • https://cdn.sqhk.co/javomekoru/jTiiatr/happy_jumpers_bahamas.pdfIn PDF document text
    • https://cdn.sqhk.co/mivijigonof/ifghTjc/pisaxita.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4413226/normal_5fe004b21a20f.pdfIn PDF document text
    • http://limelusefi.iblogger.org/65086200339.pdfIn PDF document text
    • https://cdn.sqhk.co/fewesiwe/cujdOjg/ringtones_and_wallpapers_for_iphone.pdfIn PDF document text
    • https://cdn.sqhk.co/mapetidul/cifjcjc/amazon_prime_now_gutschein_erstbestellung.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421210/normal_606e9b00eb575.pdfIn PDF document text
    • http://xosikuxevezi.22web.org/3072261109.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367273/normal_60582dfd81cf2.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://daripesobad.epizy.com/72372917969.pdfIn PDF document text
    • https://51da6a7d-ee05-4a49-87ee-1b74af3aeb07.filesusr.com/ugd/b80405_54b0e804858f4880ab883d812c4e4171.pdf?index=trueIn PDF document text
    • https://78fa80b2-8629-447b-ad63-53e91e8d4948.filesusr.com/ugd/8f02de_c18361c1402c4343a18f56f7cc9c7375.pdf?index=trueIn PDF document text
    • https://5862e4ea-63a6-4c92-af93-e06d02d1a664.filesusr.com/ugd/eaa371_22a574f2bb2843308f3c5fd14fa5b52e.pdf?index=trueIn PDF document text
    • https://aca292c6-a3ee-4c96-b4c9-db15c8eca1b9.filesusr.com/ugd/cd1d52_0c9bfc5c7d664051b5122e7e16fcb088.pdf?index=trueIn PDF document text
    • https://d1ee23ee-9ccf-45b0-80ef-1e1ff1f657c4.filesusr.com/ugd/9ef0c3_f8c9de542e0a436ba87da1907fe42fb4.pdf?index=trueIn PDF document text
    • https://afa032df-bfad-47da-a9c8-c79260182993.filesusr.com/ugd/6f9b04_73b4db1c0b954ad1a4780ef533bb4dcc.pdf?index=trueIn PDF document text
    • https://0491f86b-060d-4f4a-be23-b0d01488777f.filesusr.com/ugd/faa7ef_118b6699883e42a5abfde795de90a524.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/559fd325-f18a-4be5-bf36-6a7f4365c35c/ring_keypad_blinking_green_battery_light.pdfIn PDF document text
    • http://bededojobafepeb.rf.gd/85258924428.pdfIn PDF document text
    • http://tuxizosog.rf.gd/difference_between_bonding_and_antibonding_molecular_orbitals.pdfIn PDF document text
    • https://cc6d8859-fc08-4100-a073-55b48c5addfc.filesusr.com/ugd/238140_6a8a48eafea946b9ae999d4eb835e8c8.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/61e649cb-3dc0-4f9d-abf3-af2b2ad52bca/sarilonofakibalo.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_off0000dc57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC57 5380 bytes
SHA-256: 553daf336517eb7f26d51be23e04424b656e11023793e34306c6622ad09b01f6
font_01_sfnt_off0000eebe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEBE 10668 bytes
SHA-256: 378158547087d176f640e3bdefbe170c7e0715116619a14c663cccad30384629