Malicious PDF — malware analysis report

Static analysis result for SHA-256 879075dcc1bc0918…

MALICIOUS

PDF

76.0 KB Created: 2021-04-28 07:59:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 547520fe85c17cc338ec1708207a3e6b SHA-1: 6674973c432d7f00959a40a9b2930ba2d7290950 SHA-256: 879075dcc1bc09185ef4e076db07c90715a625b3c5d71a876f11bf221699a81e
166 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The document body contains obfuscated text and a URL that appears to be part of a link farm, suggesting an attempt to direct users to malicious content. The presence of external URIs and the 'ML_NYX_PDF_MALICIOUS' heuristic strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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=rip+curl+rifles+midsize+tide+watch+instructions PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4389571/normal_6009161c65ae0.pdfIn PDF document text
    • https://cdn.sqhk.co/duwenaxiseve/igiionI/puxofurusu.pdfIn PDF document text
    • https://cdn.sqhk.co/kajemuwasutu/QgjjdtD/grand_crime_gangster_android_gameplay.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471710/normal_602bb2e056509.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369933/normal_6039dcff5d698.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490369/normal_5fd6c64d91d06.pdfIn PDF document text
    • https://cdn.sqhk.co/saxamabewido/1xgdF9q/kindergarten_curriculum_guide_free.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459777/normal_5fd8f76e8ce49.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420260/normal_5fd38ae89b0f5.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4455658/normal_5ff56f9bb18f2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450152/normal_601c941933c03.pdfIn PDF document text
    • https://s3.amazoIn macro / runtime command snippet
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/mefadedosuw/mindfulness_guided_meditation_videos.pdfIn PDF document text
    • https://d21da297-2d1c-4020-882f-059d99c29dc9.filesusr.com/ugd/3724a2_2065b14cca5d48e7ac8988f744573815.pdf?index=trueIn PDF document text
    • https://1fa67a36-2e8b-44cc-a955-751d80433762.filesusr.com/ugd/d85e51_0abd243854454b71b2eed7f1a8be0063.pdf?index=trueIn PDF document text
    • https://8acf0fc4-2da8-4686-9788-d7840b5449fc.filesusr.com/ugd/fab691_b88cff8ebbc447bd8c109426de4a7ac1.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/eebc1782-a43f-45a0-926d-0ff86f6c1f69/a1c_11.7_conversion.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4a889292-b740-45d9-aa97-a1a08040b248/fawitosojokejijebipim.pdfIn PDF document text
    • https://c1d61d78-9bae-425c-b347-ee91470fe4f1.filesusr.com/ugd/60933b_dc8000f41a164708a3739bb0e66d1b60.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tumuzu/85976705085.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/975b1263-9d94-424f-ae24-2faecfa0634c/business_communication_class_activities.pdfIn PDF document text
    • https://d0aee4dd-c5bf-4c29-adcf-3aa844f59ef3.filesusr.com/ugd/193d13_e1eda52ad49b47c18e2171bfe2a50ceb.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_off0000e980.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE980 5544 bytes
SHA-256: 8e2ec101b0b1fdffd2a154a8253c06a40a4751ca3c4ec4f819c99ad2d659eaa2
font_01_sfnt_off0000fc51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC51 10780 bytes
SHA-256: 26679ddb026f789c3577bf93d31d575650504fb5ec3eaa0ed02279730d9e99b0