Malicious PDF — malware analysis report

Static analysis result for SHA-256 e51cc9795a7e8c99…

MALICIOUS

PDF

71.5 KB Created: 2021-10-02 23:24:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 28dadb510c692dd9d9bdfd5d30f2a150 SHA-1: ec1b3ba14d54e4eeee410478b30b2fca2b5c1244 SHA-256: e51cc9795a7e8c99affcca4ecf978780087da020107b04c4772d6beb6b336f0a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with a significant heuristic identifying it as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware. While no scripts were directly extracted, the PDF structure and embedded links suggest an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

Heuristics 5

  • 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 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 http://dison.cn/filespath/files/20210909235457.pdf In PDF document text
    • https://infotechloyalty.com/bot/ckfinder/uf/files/doxozasutatolifafopo.pdfIn PDF document text
    • http://konferencii.org/web/uploads/assets/file/kivadiwuwazil.pdfIn PDF document text
    • http://amadpich.com/userfiles/file/wasazijijaz.pdfIn PDF document text
    • http://thietbiantoanttk.com/uploads/files/sixikafivemilekavidab.pdfIn PDF document text
    • http://www.rpv-drachten.nl/files/file/mugetiwulapop.pdfIn PDF document text
    • http://dd-eng.com/files/files/dopegizolamol.pdfIn PDF document text
    • http://hoaiduc.edu.vn/ckfinder/userfiles/files/80056108601.pdfIn PDF document text
    • http://beiks.info/public/file/73554092655.pdfIn PDF document text
    • http://dglytbt.com/upfolder/e/files/20210926003229.pdfIn PDF document text
    • https://alrukn.co/userfiles/files/43836962319.pdfIn PDF document text
    • https://genia-groupe.fr/images/files/bidemubonopilesojaku.pdfIn PDF document text
    • https://monyetjoget.com/contents/files/36380567794.pdfIn PDF document text
    • http://lev-steklo.ru/userfiles/file/lolagilatovo.pdfIn PDF document text
    • https://www.miotsukushi.or.jp/system/ckfinder/userfiles/files/parokogupokawakewijo.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/161352c438777c---25651061866.pdfIn PDF document text
    • http://winkeleninzundert.nl/uploadimages/files/56102981397.pdfIn PDF document text
    • https://taptigrihnirman.com/singhania/downloads/file/nuxuz.pdfIn PDF document text
    • https://egokituz.eus/files/galeria/files/gizedevifegakagegu.pdfIn PDF document text
    • http://gyermekhaz.hu/Content/site_images/files/wewarovilozugumenagox.pdfIn PDF document text
    • https://thuanxuongmonmb.com/admin/webroot/upload/image/files/pavoxemanawu.pdfIn PDF document text
    • https://tungafilm.com/dorceiys/ckfinder/userfiles/files/21000060632.pdfIn PDF document text
    • https://www.abandassociates.com/ckfinder/userfiles/files/80890003448.pdfIn PDF document text
    • http://okuninka-biale.pl/userfiles/file/61104254039.pdfIn PDF document text
    • http://feketemeheszet.hu/UserFiles/File/romagiwosadutuwelomukixo.pdfIn PDF document text
    • http://dastone.ru/userfiles/file/rezorupexaxuruvow.pdfIn PDF document text
    • http://flamefitnessstudio.com/cewit/images/file/29185571117.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=how+to+scan+multiple+pages+with+windows+scanPDF link annotation
    • 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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b67d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB67D 15604 bytes
SHA-256: 722e4a369ae128bde11c0c66d6b09266f1409689118d3be182d7f8de147f9630
font_01_sfnt_off0000de2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE2C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f643.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF643 11036 bytes
SHA-256: b6af7a736fa6db329d33a18a6610bab38bdc75bd784b42d6d38cef2c61df0c26