Malicious PDF — malware analysis report

Static analysis result for SHA-256 a83538debd38c8cf…

MALICIOUS

PDF

83.3 KB Created: 2021-03-17 03:44:56 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 829e42f8fd28d9e30267d864c8b09633 SHA-1: 1f60bbb3cde43bb8f77b0f78a53959202de31443 SHA-256: a83538debd38c8cfc89b1d58e08bc00bc2622a89f2eaccc585272d8ed12d8b30
126 Risk Score

Malware Insights

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

This PDF document is classified as malicious, with a high ML score and ClamAV detection as a phishing trojan. It contains numerous embedded URLs, including one pointing to "https://jacksth.ru/award?keyword=core+java+multiple+choice+questions+with+answers+pdf", suggesting a phishing or credential harvesting attempt. The document's structure and the presence of many links indicate it functions as a link farm designed to redirect users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://jacksth.ru/award?keyword=core+java+multiple+choice+questions+with+answers+pdf PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4420239/normal_60074480c57c1.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4417990/normal_600192e8be9e0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4473971/normal_5fe30f21a605a.pdfIn PDF document text
    • https://cdn.sqhk.co/mipijotom/cQgdDhe/regulated_capitalism_definition_ap_world_history.pdfIn PDF document text
    • https://cdn.sqhk.co/movumatoz/eHQfiaO/metal_soldiers_2_mod_game_download.pdfIn PDF document text
    • http://bowuvudofi.scienceontheweb.net/watatosesomevuvape.pdfIn PDF document text
    • https://cdn.sqhk.co/dafagupovo/hg8nVgi/camera_raw_canon_eos_60d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382958/normal_6010efaa59592.pdfIn PDF document text
    • https://cdn.sqhk.co/bosamame/gf5hfNf/chasing_the_king_of_chess.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413465/normal_5fd8583773d5b.pdfIn PDF document text
    • http://bokukot.22web.org/lakufosobonekodojo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/tikofaketonub/all_photo_size_list.pdfIn PDF document text
    • https://84d51d8d-5932-465a-b044-5d36dace581c.filesusr.com/ugd/98e2de_f6ca7308fe944c80968d563ef16f8ae4.pdf?index=trueIn PDF document text
    • http://dinamol.epizy.com/new_headway_beginner_student_book_download.pdfIn PDF document text
    • https://s3.amazonaws.com/dixaleko/siwonuxowot.pdfIn PDF document text
    • http://wirowobizofox.epizy.com/how_to_use_a_barnett_jackal_crossbow.pdfIn PDF document text
    • https://s3.amazonaws.com/xuzakob/burnham_boiler_distributors.pdfIn PDF document text
    • https://02408c19-b9f6-4996-a596-1d5b7e46c8d3.filesusr.com/ugd/c83fdb_8847922924874ff7a49912829d697a23.pdf?index=trueIn PDF document text
    • http://salajire.onlinewebshop.net/rafepexejujitozulu.pdfIn PDF document text
    • https://s3.amazonaws.com/wiwamoxamo/27979741678.pdfIn PDF document text
    • http://gegilifopom.myartsonline.com/15516863411.pdfIn PDF document text
    • http://xazopufegi.onlinewebshop.net/applied_mathematics_volume_2.pdfIn PDF document text
    • http://beliraguw.onlinewebshop.net/zezeselunenogiledaxaziwo.pdfIn PDF document text
    • https://bb55feb6-a0c4-48ae-8f72-aea2c45912f8.filesusr.com/ugd/b9801a_776aae805f7442a7a9f0f7e953c87120.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/wipotegadodorek/sopaxu.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_off000103fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103FA 5652 bytes
SHA-256: 7b2f6a39ac2af698f874aa648c14fa2bee3ed714643a13686d4f43b936d60950
font_01_sfnt_off00011718.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11718 11808 bytes
SHA-256: 1cacbd6deecc481f75e096be2af55b3659bad41ea683299952d446108b583321