Malicious PDF — malware analysis report

Static analysis result for SHA-256 407f2d059f87988f…

MALICIOUS

PDF

77.9 KB Created: 2021-03-13 14:53:51 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-30
MD5: f1a625bb101ca1648d9401c9da523483 SHA-1: a3ef6b3d2434f28424ec33c4efefcbd1590f6e9e SHA-256: 407f2d059f87988f42d08c66547cc2bc563983b4b54a353236bfcd013b9e7043
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file is identified as malicious by ML classifiers and ClamAV, specifically as a phishing or trojan variant. It contains numerous embedded URLs, many pointing to disposable hosting, and a heuristic indicates it functions as a link farm. The document body, though heavily obfuscated, suggests a lure related to 'basic Korean language words', likely a pretext to drive users to the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://jumiwimov.ru/strik?utm_term=basic+korean+language+words PDF link annotation
    • http://housefashion.ru/offshore_engineering1j3yt.pdfIn PDF document text
    • http://avtoshkola-region26.ru/did_thrawn_know_palpatine_was_a_sithrcynp.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402938/normal_601bc2a7d20b1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452834/normal_5fd88d667b320.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4371786/normal_5fe527ec1708f.pdfIn PDF document text
    • http://filemarker.store/takeuchi_tb230_operators_manual70viv.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480880/normal_60275695a4117.pdfIn PDF document text
    • http://kukushka.space/tutu_app_not_workingnj33z.pdfIn PDF document text
    • http://confirmationhelpcenter.com/to_leave_a_void_meaning_in_english27wmt.pdfIn PDF document text
    • http://whalesqpa.fun/exploring_photosynthesis_and_plant_pigments_lab_report68w3y.pdfIn PDF document text
    • http://podarokinsta.online/rehras_sahib_path_in_english_download62ux7.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4464067/normal_60060287e77db.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374963/normal_5fe62d028bfd5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415951/normal_603a72e560ef7.pdfIn PDF document text
    • http://creditscoreusa.info/tugeresiluronawiduxufakewax88.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4488322/normal_5febdc0cd53ef.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/9779ea73-cb52-4e9d-afe4-81975d679eca/tepitesuzogawurapukodarof.pdfIn PDF document text
    • https://s3.amazonaws.com/dotivaf/2019_all_telugu_movie_naa_songs.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/71dccf81-83cd-4670-825a-9cbdbbf05aa4/what_is_boundary_condition_in_ansys.pdfIn PDF document text
    • https://s3.amazonaws.com/jebokizez/trainer_for_blades_of_time_pc.pdfIn PDF document text
    • https://s3.amazonaws.com/pubopelej/rawesivama.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bd16ac51-e764-4ae2-a445-b8401cd7270e/is_there_a_how_to_train_your_dragon_5.pdfIn PDF document text
    • https://s3.amazonaws.com/jadudusujuje/conceptos_de_derechos_humanos_de_diferentes_autores.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2ed3c212-77ef-420a-83ea-ba26acdb24b2/10112535893.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5aa03d24-0f04-4c74-89f5-e951e44f2330/how_much_does_a_mile_of_road_cost.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_off0000efd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFD0 5312 bytes
SHA-256: 0677219dbdfc13b5d44c9f57e36cd5d3c0a75e442903513214f4d8455bb8c812
font_01_sfnt_off00010204.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10204 11760 bytes
SHA-256: 9f4db89be71b47515e0ef18557de7c7ab66ec99e5a1b4c82bebc7f52ce5c18e5