Malicious PDF — malware analysis report

Static analysis result for SHA-256 b870b0dc797a4a1d…

MALICIOUS

PDF

90.1 KB Created: 2021-04-30 22:35:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: e6db2105e5fe97e8a49843128e298008 SHA-1: 112d6a2b7f944d7d42f12197f17333701c80c3f9 SHA-256: b870b0dc797a4a1d8360cc65427a1d5447a585c0c8bd2d4544d4aa37c5b6f6f4
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 0.9992

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=july+8th+secret+language+of+birthdays PDF link annotation
    • https://cdn.sqhk.co/jorimalid/egcbphc/feather_drawing_template.pdfIn PDF document text
    • https://junurewumopu.weebly.com/uploads/1/3/2/7/132740614/jekifegugi-sofagebudu-nabebolatejunel.pdfIn PDF document text
    • https://cdn.sqhk.co/vonezositixi/jh2uie1/williams_space_station_pinball_machine_for_sale.pdfIn PDF document text
    • https://cdn.sqhk.co/lopovekis/o2ZZExJ/tchaikovsky_june_barcarolle_sheet_music.pdfIn PDF document text
    • https://nebuxegakox.weebly.com/uploads/1/3/4/4/134404726/8662995.pdfIn PDF document text
    • https://rasuwexidu.weebly.com/uploads/1/3/4/6/134634130/fubalemugabami-ravatim-pafibo-wesomopidiwedo.pdfIn PDF document text
    • https://sowidokobixu.weebly.com/uploads/1/3/1/8/131856306/263f0b3.pdfIn PDF document text
    • https://mukiniga.weebly.com/uploads/1/3/4/3/134318698/5608730.pdfIn PDF document text
    • https://cdn.sqhk.co/jibetovo/gfiihei/japan_train_simulator_games_online.pdfIn PDF document text
    • https://cdn.sqhk.co/modajili/c1hggck/nuzuv.pdfIn PDF document text
    • https://cdn.sqhk.co/labojime/GjgcLid/23842601147.pdfIn PDF document text
    • https://cdn.sqhk.co/wafavalufa/wzvghnd/vixefuxogigot.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/ec4439eb-de1f-42c0-9e46-75c5d270da41/pajanutujazoraru.pdfIn PDF document text
    • https://s3.amazonaws.com/sinadi/muwifimurerazipexosur.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d41d8e7f-b61e-4e74-8c24-1c922b296334/85853149642.pdfIn PDF document text
    • https://s3.amazonaws.com/fobupojowojon/jtbd_interview_template.pdfIn PDF document text
    • https://s3.amazonaws.com/jugobimuraje/1812971595.pdfIn PDF document text
    • https://457cefd1-268f-49c0-9ca4-ced5ac281e6b.filesusr.com/ugd/983758_481c0ed19dc3463c82d747647deacdf4.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/07ed86ac-8992-4fd7-a9b8-3c64d627182e/xokuva.pdfIn PDF document text
    • https://s3.amazonaws.com/zisulamisozoto/dakamuz.pdfIn PDF document text
    • https://70fbc5f3-53e4-4072-9ff7-a5862d19847b.filesusr.com/ugd/bb3bf9_b14e2e64b3a64b0ca1892177c0539f21.pdf?index=trueIn PDF document text
    • https://911f1565-2faa-4874-b261-330d521e7362.filesusr.com/ugd/f46427_4e4ec71298454be78874c7042f0c396b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/177fc111-0cf0-46f1-99a4-ac23c282b969/mississippi_drivers_license_road_test.pdfIn PDF document text
    • https://s3.amazonaws.com/sosupejuxofedo/bihar_blank_map.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a3b381ab-6e1c-47c4-8ca6-0611e9410321/king_kutter_tiller_warranty.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_off0001224d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1224D 5708 bytes
SHA-256: 624f4b90b5006c87f3485cac4c67f9f8beaf56519e9467a09091c231213c18e7
font_01_sfnt_off000135b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135B9 10812 bytes
SHA-256: c2d6ac28176ae2d711ea5b92e5f43ae52f9813ca6321810c4c677cc8f761eba0