Malicious PDF — malware analysis report

Static analysis result for SHA-256 a94e016fdafd31d8…

MALICIOUS

PDF

82.0 KB Created: 2021-05-13 16:25:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 7c1b24f6cbaa55ff1a2d0ed60890f709 SHA-1: 41ba411a2ae6527b9d7a0fad0ef31b3d9b175a5a SHA-256: a94e016fdafd31d82795da20604a02b9a09510ee5cca26b52050e04fb08a5152
126 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to disposable hosting, indicating a link farm or SEO manipulation tactic. The ML classifier flagged this PDF as malicious with high confidence. While no scripts were extracted, the presence of numerous external URIs suggests an attempt to redirect users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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://bologen.ru/strik?utm_term=samsung+me16h702ses+parts+diagram PDF link annotation
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/e76198c6-8990-4368-abb9-dd9840aa158d/xirarinowukomewoselixowe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ec5b88cb-a1b0-41b3-9f39-eb4286799727/what_is_value_education.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/49897ad0-7b16-4580-8ad0-bc47fe8b9b73/dometic_brisk_air_ii_15000_btu_amps.pdfIn PDF document text
    • https://s3.amazonaws.com/dibedamoka/warehouse_inventory_access_database_template.pdfIn PDF document text
    • https://b3a8b944-ddec-4d17-9b53-5a1c05c66d8c.filesusr.com/ugd/314503_32ac8030dfb240f88c31ca33edf17677.pdf?index=trueIn PDF document text
    • https://c2093f15-f4fb-4bda-9582-db5404103fa6.filesusr.com/ugd/b28561_d95ceafc150b4454b904a065984ed791.pdf?index=trueIn PDF document text
    • https://67dec473-0a9c-497c-80b1-62a4c84c5046.filesusr.com/ugd/0aab01_ac7fa2cc59494c67844f0e658b5147cb.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/1e1173f5-9836-4aa9-bf9e-e2b826d295a1/sat_subject_test_math_2_curve.pdfIn PDF document text
    • http://bapexuzajo.epizy.com/rutumi.pdfIn PDF document text
    • https://s3.amazonaws.com/vudivuzakal/dafebapudakarobiwigase.pdfIn PDF document text
    • http://xapuzafuzokuw.rf.gd/fisika_medan_listrik.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/578c9285-49e2-4e9f-81ec-7a090405a34a/7146979956.pdfIn PDF document text
    • https://b1c30c75-ab46-439a-884d-3836ae4b8a49.filesusr.com/ugd/2d1648_2deec0b91f2246b6ab531ae80080f6a1.pdf?index=trueIn PDF document text
    • https://76bf09fe-c378-4d6f-baa9-beaf48595a8b.filesusr.com/ugd/61567a_ef0dd12c04d747cb9bfc1b3f3f9eccd2.pdf?index=trueIn PDF document text
    • https://13006a6e-9b3f-4191-9e3f-064114488741.filesusr.com/ugd/34464a_24b5436f2fd747d4857c332f9fa05d54.pdf?index=trueIn PDF document text
    • https://21a67f6d-2aea-439f-a910-ed4feb6be009.filesusr.com/ugd/173616_513bca8c5cce498b9dab65f688625f83.pdf?index=trueIn PDF document text
    • https://0b670cc3-d94b-4117-8b98-7ce677fb6c21.filesusr.com/ugd/7bc559_d83f26cf3bb64e91965e45978a3035dc.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/3c73608d-c036-465f-bfe2-216fc8078b46/nomadic_furniture_book.pdfIn PDF document text
    • https://s3.amazonaws.com/zazelujeju/bosch_security_camera_software.pdfIn PDF document text
    • http://lumajenav.epizy.com/36223598489.pdfIn PDF document text
    • https://s3.amazonaws.com/jozaponi/bikini_body_guide_dieta.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_off000100b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100B8 6004 bytes
SHA-256: 5e10bb58fdec94167c0fd54404ccffe2344cb09ae44b94b617906d8b7f35d5f6
font_01_sfnt_off00011506.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11506 11108 bytes
SHA-256: 6a1dfb96d3049258c1635b06ad10844a372b5b21c67941b738dc06821555e3c8