Malicious PDF — malware analysis report

Static analysis result for SHA-256 3539fc16f129ef19…

MALICIOUS

PDF

82.7 KB Created: 2021-04-07 02:58:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 73d0792bc9f5dbd9f5d7f3e4b2445b9a SHA-1: 74ff80b7dbaf78103dc8b53f667d94fe4dd0c12f SHA-256: 3539fc16f129ef196e6f95b8f57c14b4ee4f6fae83cae70cc92f9ee69dc68744
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

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 0.9990

Heuristics 5

  • 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 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://baarspo.ru/123?utm_term=budgeting+worksheets+for+adults+uk PDF link annotation
    • http://itmax.info/constitucion_politica_de_los_estados_unidos_mexicanos_1857_articulose65kq.pdfIn PDF document text
    • https://cdn.sqhk.co/gixedomawa/Ehdjdhf/extinction_rebellion_latin_america.pdfIn PDF document text
    • http://skidki-day.site/32365041839fiahj.pdfIn PDF document text
    • https://cdn.sqhk.co/gawagunikuw/heCejdX/wagas.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4461511/normal_604e8f5f24c5a.pdfIn PDF document text
    • https://cdn.sqhk.co/pivokazi/gdVheii/97751503191.pdfIn PDF document text
    • https://cdn.sqhk.co/gifexajed/6jjgef0/wapiwapotaguzapimudaxuv.pdfIn PDF document text
    • https://cdn.sqhk.co/sejujona/gfwkpgd/28375665182.pdfIn PDF document text
    • https://cdn.sqhk.co/viwiratoposu/iegjiMs/hyper_ball_legends.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384160/normal_6056927fcc3e6.pdfIn PDF document text
    • https://cdn.sqhk.co/xunixenovapi/Rhbbs0D/drift_hunters_unblocked_crazy_games.pdfIn PDF document text
    • https://cdn.sqhk.co/bodujemep/ickwje8/story_cubes_free_printable.pdfIn PDF document text
    • http://yourbigdick.space/cash_and_accrual_basis_of_accountingh8hen.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409118/normal_603fa5b7c20c0.pdfIn PDF document text
    • http://changepass.online/ukulele_strumming_patterns_4_4d4fg6.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4468571/normal_6003752de3daa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/cf2d3799-3662-42c4-b48e-9fac3ee60e02/who_needs_osha_certification.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/682a610f-62b5-4eb7-be8c-598960006559/how_to_change_the_toner_on_a_brother_mfc.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/71ad771f-7e6a-4ae3-bf87-4ec2387ad1f9/my_cloud_storage.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/54e8ac4e-caae-4e4c-b85a-fce8f96b2a3b/insinkerator_repair_tool.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6ad1e09d-a2da-48a8-9e3e-b07edb4964c3/wix_total_addressable_market.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ff88de56-8243-45c5-8693-6d89755fbdef/excel_vba_find_string_in_range_of_cells.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/90cff2ef-aacf-4276-8939-6f07aa8504d4/how_did_the_new_deal_recovery_the_great_depression.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/43a947ee-2a68-441b-ac52-697fbcf61ef2/how_to_reset_kenmore_elite_he3_washer.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_off0000f5b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5B6 5256 bytes
SHA-256: b7263e203cfbc5ad51548d0e4e8e4f72e6aa70f69b77184af363d37530673754
font_01_sfnt_off000107a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107A1 11040 bytes
SHA-256: 8eca3d0a354d3f66d4288c0374156d1b72c0cd7099bc3114be2dd94b68e251ac
font_02_sfnt_off00012d5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D5E 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3