Malicious PDF — malware analysis report

Static analysis result for SHA-256 883a73f8fdc251f9…

MALICIOUS

PDF

78.0 KB Created: 2021-03-20 06:03:00 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: a3ca5338fd0122e367eb240de04d1207 SHA-1: cd99cb9cd684482fe6ad891ed2a445401b7847b6 SHA-256: 883a73f8fdc251f9a524c35e5e6771d61734c35063ac917280e3b6f28260154f
126 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. It contains numerous embedded URLs, with a primary one pointing to 'zajinet.ru', suggesting a phishing or malware distribution attempt. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and 'online form', reinforcing the lure. No scripts were extracted, but the overall structure and URL reputation point to a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://zajinet.ru/123?utm_term=pkvy+online+form PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4487927/normal_6053bdf5075ee.pdfIn PDF document text
    • https://vobikonim.weebly.com/uploads/1/3/5/3/135390296/b5bbdff.pdfIn PDF document text
    • https://vipagavufedolaz.weebly.com/uploads/1/3/5/3/135350232/remosadazefegu-gidokaxi.pdfIn PDF document text
    • http://pofuxubilet.sportsontheweb.net/antonyms_words_list_with_meaning.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4461207/normal_604dc54b60615.pdfIn PDF document text
    • https://cdn.sqhk.co/jupozaregu/gejajdy/airport_emergency_crash_rescue_trucks.pdfIn PDF document text
    • https://digonowokeke.weebly.com/uploads/1/3/1/8/131856318/wexufitixirufofes.pdfIn PDF document text
    • http://wegoluxetas.scienceontheweb.net/muzoduberazalapan.pdfIn PDF document text
    • https://cdn.sqhk.co/someteku/KheXdgd/zivibununex.pdfIn PDF document text
    • http://toteganutiv.66ghz.com/95712762450.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4425214/normal_5ff64ffebe932.pdfIn PDF document text
    • http://sawemawe.mywebcommunity.org/hp_officejet_2620_ink_cartridges.pdfIn PDF document text
    • https://cdn.sqhk.co/wunokebewoz/getgj7r/character_stat_generator_5e.pdfIn PDF document text
    • https://xogepojofaridel.weebly.com/uploads/1/3/2/7/132741214/wurunijogifuv-bapikijoja.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://wotidupodugi.myartsonline.com/xubidiboxudazazodez.pdfIn PDF document text
    • http://zipituvopedisi.rf.gd/coleman_cpx_6_lantern_not_working.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/788780fd-ad22-4e5f-9014-fa49c50d8e9a/92806003558.pdfIn PDF document text
    • http://wubazinosimisod.rf.gd/snow_white_with_the_red_hair_season_1_episode_13_vimeo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b82200ca-12cb-4f65-abd3-a40a613048d9/67974988057.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/20ac7813-a19e-4f8e-b800-88203d720a0e/constitucion_politica_de_los_estados_unidos_mexicanos_1857.pdfIn PDF document text
    • http://pitolujebenim.epizy.com/book_review_of_nancy_drew_the_hidden_staircase.pdfIn PDF document text
    • http://rimamosapike.epizy.com/jutavegulitotewov.pdfIn PDF document text
    • http://tiluxusimutine.atwebpages.com/three_mistakes_of_my_life_book_in_hindi.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e7fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7FC 4460 bytes
SHA-256: c44fc6217d7d9df3b4197f337966ec661609b57d57f4f80ecfb478d00b5ca060
font_01_sfnt_off0000f6fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6FE 10800 bytes
SHA-256: e5e855c4fdaa36c72ebd4dc8314b780732a0b7a7305af393cb1e7a1b36b7a5ad
font_02_sfnt_off00011c0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C0D 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34