Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d786e1758b85487…

MALICIOUS

PDF

107.9 KB Created: 2021-05-06 11:37:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: b65ae7f87d43bd87eab10d517078a074 SHA-1: 274906c38c5fa4319f9a2d7579361ae4b5ccc59d SHA-256: 8d786e1758b8548759b6fe877deeed8ef639e7b41dd7219fc4b1d23ab2f92953
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many pointing to disposable hosting, and one suspicious URL (vilenefex.ru) that is not yet classified. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded content, though heavily obfuscated, suggests an attempt to disguise the malicious nature of the document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://vilenefex.ru/strik?utm_term=why+did+texas+fail+as+a+spanish+colony PDF link annotation
    • https://cdn.sqhk.co/posojuvapono/figEjCN/stacker_pills_dollar_tree.pdfIn PDF document text
    • https://cdn.sqhk.co/pijujuweg/hieggji/towulibigefufemo.pdfIn PDF document text
    • https://cdn.sqhk.co/mudonisogub/WiaGbWQ/21651595700.pdfIn PDF document text
    • https://cdn.sqhk.co/sowodopevew/diahihb/46491144418.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://7f1888b6-cdab-4603-9914-1cf81a8b29aa.filesusr.com/ugd/6846fe_de3fb0e4d012427788c22af49307aa45.pdf?index=trueIn PDF document text
    • https://bd7a0a6f-bbfd-49cc-ba41-c3f2778102d9.filesusr.com/ugd/9ea91e_a2b82b5a930645a5801b7082591d3b85.pdf?index=trueIn PDF document text
    • https://c6111751-42b6-464f-a8b1-832d492ff999.filesusr.com/ugd/3d0627_54927023bbe6460293ebab9200fc600d.pdf?index=trueIn PDF document text
    • https://9b08d158-0e0f-4203-9b31-e1272d977b1c.filesusr.com/ugd/086daf_a658dcfaf491464589f651cebd37875c.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/3cc78c72-f617-4c1c-9649-2c62a2af002b/raterarevonuxawetoxi.pdfIn PDF document text
    • https://c208ddc4-37ec-4cef-823d-79aeaa8cd68a.filesusr.com/ugd/d34c4d_8c20990581434d3582718f1e349e2de9.pdf?index=trueIn PDF document text
    • http://zegorurowi.epizy.com/sat_writing_and_language_practice_test.pdfIn PDF document text
    • http://waketekedoveke.epizy.com/xogidepijofotopokagapep.pdfIn PDF document text
    • http://kixixiwibatogit.epizy.com/ielts_speaking_2018_september.pdfIn PDF document text
    • https://7e8267f5-6380-480e-ad72-df526eaefc07.filesusr.com/ugd/cbe325_5b1cec5db07a4f4ebc0ef60ddb4ac8e1.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/7a90eac4-5328-4735-aeb6-d25113bcb2a0/raduwokerukej.pdfIn PDF document text
    • http://luxorofanogefa.rf.gd/parasitic_diseases_of_wild_mammals.pdfIn PDF document text
    • https://538d8494-0c7d-401a-b890-0485f6bc7bca.filesusr.com/ugd/29c71c_15cee2a870324f0cb91f8e6cdd075132.pdf?index=trueIn PDF document text
    • https://a43ab9c2-5efb-4cee-ac06-b782a0f5e207.filesusr.com/ugd/4826f5_0fd993f23eb3430181950dcbf3116944.pdf?index=trueIn PDF document text
    • http://vuripuwap.epizy.com/the_count_of_monte_cristo_short_version.pdfIn PDF document text
    • https://9170d309-caca-4186-8987-bf6b40ce219c.filesusr.com/ugd/baef12_39e662ab2a2643f8b32bc74e92f6d174.pdf?index=trueIn PDF document text
    • https://793776f3-68b4-44d3-947a-596ce2c6f652.filesusr.com/ugd/4e977a_74fe59b18a234a2db47c33b1d3b80534.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/a384b2f7-3dd0-452d-8e2c-b1e5b125a7a6/how_to_hack_money_farming_simulator_2019.pdfIn PDF document text
    • https://d064ede3-316f-4d13-8ec5-014b2136b3bd.filesusr.com/ugd/154db6_a3b02e4ed1c14c54a1540a9d0f41d134.pdf?index=trueIn 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_off000166e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x166E6 5332 bytes
SHA-256: 44b56d89a464e1c0645bcfda5dd84c42656b9242754d64f65df0c59e480419a6
font_01_sfnt_off00017929.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17929 12404 bytes
SHA-256: 940e7eed301910bd806ef6d0a5b7ed574e1afce86383ebd88a8726bd4649329c