Malicious PDF — malware analysis report

Static analysis result for SHA-256 9381ba1cc43f6b90…

MALICIOUS

PDF

81.3 KB Created: 2021-09-13 09:03:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: e432ce5d9a08c639c9f1a00aabf6b0fe SHA-1: b2bfa1e5946f1fd47e8e439f207d4d388f8b75a1 SHA-256: 9381ba1cc43f6b90521f7a02aef0b82db1a8f9aed9903320b92e2fdab8527db2
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a phishing or trojan-like behavior. The presence of numerous links, many pointing to PDF files on different domains, suggests a link farm designed to obscure the ultimate malicious destination. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically calls out this behavior, and the embedded URL with 'game nba 2k14 apk download' in the UTM term indicates a lure to trick users into downloading a file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://le-nora.com/userfiles/file/walol.pdf In PDF document text
    • http://gardatrans.com/content/Files/tawavuf.pdfIn PDF document text
    • http://www.tamtrebinhminh.com/public/files/27340668950.pdfIn PDF document text
    • http://gld-lining.com/user_img/files/libaxi.pdfIn PDF document text
    • https://www.pactforfamilies.org/ckfinder/userfiles/files/ziwujometopunuwosedewogux.pdfIn PDF document text
    • https://onecre.com/images/content/files/pegeje.pdfIn PDF document text
    • http://talcmanagement.com/uploaded_files/userfiles/files/33887667174.pdfIn PDF document text
    • https://stomatoloska-ordinacija-rijeka.com/files/sevot.pdfIn PDF document text
    • http://www.mamafoundation.cz/ckfinder/userfiles/files/mokijizabumiwufil.pdfIn PDF document text
    • https://iveducentar.com/uploads/assets/file/kelowalijadiwekubufobo.pdfIn PDF document text
    • http://mdknoodles.co/uploads/files/81418208993.pdfIn PDF document text
    • http://lasantitosrestaurant.com/userfiles/file/85427877262.pdfIn PDF document text
    • http://crisismobile.com/ckfinder/userfiles/files/88188672231.pdfIn PDF document text
    • http://spiregene.com/image/files/20210901_100116.pdfIn PDF document text
    • https://serrechevalier-skifun.com/imagesfile/56349353863.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139222f434ed---57059587180.pdfIn PDF document text
    • https://mastirz.com/userfiles/files/zanotejeguwusakivumer.pdfIn PDF document text
    • http://asckhn.com/acskhn/userfiles/file/75659544402.pdfIn PDF document text
    • https://hosvagyok.hu/userfiles/file/bamasawewawuzufejo.pdfIn PDF document text
    • http://dulichtantai.com/files/uploaded/files/14100211645.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613b04ce2a351---20426540290.pdfIn PDF document text
    • http://symbioticlifetech.org/attfile/fckimg/file///202109082282_46322006.pdfIn PDF document text
    • http://consoles-a-gagner.com/fckeditor/userfiles/file/74677809551.pdfIn PDF document text
    • http://addisonplaza.abwingsmd.com/uploads/files/xebezazefetipevuwo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=game+nba+2k14+apk+downloadPDF 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_off0000d9d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9D8 10700 bytes
SHA-256: 609092c50b250183927deaa1ed147585aa1a45440d99eaff6e83ba051006e909
font_01_sfnt_off0000f24f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF24F 17612 bytes
SHA-256: 708f09d3178ab7f251a42f6b6cf58c736af65de6e44b9750179c3ae56a7829bc
font_02_sfnt_off00011fa7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FA7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1