Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c1dac0687f181bd…

MALICIOUS

PDF

90.9 KB Created: 2021-06-04 10:57:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 6ec9190499ede1decaf6f121c59ded0d SHA-1: 72b96f6512ca39926c9b06a0a84e532234356fd9 SHA-256: 8c1dac0687f181bdcb420bfd1995d44bd5497a4711a68e82ff9f4e665171faff
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 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://crewmak.ru/pbw?utm_term=what+is+comparative+form+of+bad PDF link annotation
    • https://sufixekanol.weebly.com/uploads/1/3/4/7/134712322/62cddf9da341.pdfIn PDF document text
    • https://xasazixasemopib.weebly.com/uploads/1/3/4/3/134306387/6987c1b4d2ae08.pdfIn PDF document text
    • https://mefivezetu.weebly.com/uploads/1/3/2/6/132681021/juveruwu-subekibofux-nedurumap-nekajuzerajijox.pdfIn PDF document text
    • https://piladokad.weebly.com/uploads/1/3/4/7/134759874/de4fcbd.pdfIn PDF document text
    • https://vabebixeteguju.weebly.com/uploads/1/3/4/2/134234611/fosabivofofikuz-junapomap.pdfIn PDF document text
    • https://zunarorukozem.weebly.com/uploads/1/3/4/0/134016655/pokoterimi_pulilamojikom_futesesejodo_vawexudujes.pdfIn PDF document text
    • https://xezagepu.weebly.com/uploads/1/3/4/9/134901129/4305771.pdfIn PDF document text
    • https://lunogowome.weebly.com/uploads/1/3/4/8/134859941/b4eb33bee.pdfIn PDF document text
    • https://gupovokezatiku.weebly.com/uploads/1/3/4/8/134878629/e8fa552bf6fb92d.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://felinemumivu.pbworks.com/w/file/fetch/144526179/wurariliridij.pdfIn PDF document text
    • http://zorisomofi.pbworks.com/w/file/fetch/144555228/bohemian_rhapsody_sheet_music_piano_free_download.pdfIn PDF document text
    • http://lufokomarib.pbworks.com/f/bissell_proheat_pet_carpet_cleaner_belt.pdfIn PDF document text
    • http://xedidovetaw.pbworks.com/f/34747599122.pdfIn PDF document text
    • http://mefijunov.pbworks.com/w/file/fetch/144414783/real_book_bass_clef_free.pdfIn PDF document text
    • http://taxexuwej.pbworks.com/f/cover_letter_for_job_application_sample.pdfIn PDF document text
    • http://poxanoralanu.pbworks.com/w/file/fetch/144422034/text_features_first_grade_lesson.pdfIn PDF document text
    • http://genarozep.pbworks.com/f/guia_de_comprension_lectora_tercero_basico_word.pdfIn PDF document text
    • http://zepadatoju.pbworks.com/f/baaghi_3_full_movie_hindi_download_pagalworld_mp4_hd.pdfIn PDF document text
    • http://zewalar.pbworks.com/w/file/fetch/144603726/9.pdfIn PDF document text
    • http://xutosop.pbworks.com/w/file/fetch/144602700/is_note_5_still_a_good_phone.pdfIn PDF document text
    • http://junerew.pbworks.com/w/file/fetch/144598821/26686355267.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00013dab.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x13DAB 19656 bytes
SHA-256: 7140c1b97298b010f3718e24f900b444efa111213d54cd782e0fdacfc14836c3
font_00_sfnt_off0000f1f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1F0 5576 bytes
SHA-256: 3018b8e4aabe39ecab3d642a77d5337929153fb73da9f54a1472504e3237d367
font_01_sfnt_off000104c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104C7 20024 bytes
SHA-256: 02b8dd3810b13ef3d727f0b21a8395500610b5f960d45e40391b15331f68b3d6