Malicious PDF — malware analysis report

Static analysis result for SHA-256 db988b6748984066…

MALICIOUS

PDF

86.2 KB Created: 2021-09-09 20:00:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 1de900a068f055567efe4cc1ad383eed SHA-1: f13432118224c9ddccd100ffb0b2d123289089e3 SHA-256: db988b674898406678b361554f02c1cac8d8baff1b8a81e34ab0f7ca8375cc0d
66 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable hosting and are likely used for SEO manipulation or to redirect users to malicious sites. The ML classifier strongly indicated maliciousness, and the PDF structure suggests a link farm designed to deceive users or search engines. No scripts were extracted, but the presence of external URIs and the link farm heuristic point to a malicious intent to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 4

  • 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://medvor.ru/uplcv?utm_term=space+station+tracker+app+android PDF link annotation
    • https://artofsurfing.com/preview/ckfinder/userfiles/files/17878136658.pdfIn PDF document text
    • http://corporatiegids.nl/uploads/files/39357360006.pdfIn PDF document text
    • https://hearing-outlet.com/uploads/files/202109071102501236.pdfIn PDF document text
    • https://fivetc.net/uploads/files/42607425570.pdfIn PDF document text
    • http://polkovnik.su/upload/file/53660316083.pdfIn PDF document text
    • http://perfekt-dom.pl/designhome/admin/userfiles/file/pudimawogavedevunubogakav.pdfIn PDF document text
    • http://liavanhaeringen.nl/userfiles/files/xevodogidiwe.pdfIn PDF document text
    • http://fewo-spreewald-schoetzigk.de/brandenburgtag/img/editor/file/75754311421.pdfIn PDF document text
    • http://bbfrontedelmare.com/userfiles/files/4878999018.pdfIn PDF document text
    • http://pcccphucvinh.com/upload/files/23242873136.pdfIn PDF document text
    • http://hvpeds.com/upload/contents/file/vovibufumud.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161350c81d3508---bebuli.pdfIn PDF document text
    • http://rszm88.com/upfolder/e/files/20210907031335.pdfIn PDF document text
    • http://penzionnakrizankach.cz/ckfinder/userfiles/files/botivoregemug.pdfIn PDF document text
    • http://balone.net/_upload/file///10016182213.pdfIn PDF document text
    • http://ilkjv.com/Images/Media/files/dulupuvixevalunurasixod.pdfIn PDF document text
    • https://ivanda-commerce.hr/userfiles/file/44713865930.pdfIn PDF document text
    • https://viktorina.ledoritulys.lt/files/33123358826.pdfIn PDF document text
    • http://moriefrusca.com/userfiles/files/46965787693.pdfIn PDF document text
    • http://gaudi.tw/upload/file/34762877834.pdfIn PDF document text
    • https://sieuthimaycafe.vn/uploads/file/87479328577.pdfIn PDF document text
    • http://aibasylhet.edu.bd/app/webroot/ckfinder/userfiles/files/85610974269.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/161393e9de5d66---tibedabubujukuzes.pdfIn PDF document text
    • http://medical-1669.com/userfiles/files/73592377532.pdfIn PDF document text
    • http://frigotechreina.com/userfiles/files/4053861320.pdfIn PDF document text
    • http://career-id.org/ckfinder/userfiles/files/61058800759.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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000edec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDEC 10628 bytes
SHA-256: 0dfb9dc59f09106918b3b341e190a3e289319e7ee7ea3f6a256876cc1070e52b
font_01_sfnt_off0001065e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1065E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011e70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E70 17168 bytes
SHA-256: 1d2778f0dfe0b7dd12fe08d899f84dc5804a9828e3681402d3338fe7fe308d4e