Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a21f239b967032b…

MALICIOUS

PDF

82.8 KB Created: 2021-09-17 20:51:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: ea9874435cd2d8ab8702f2644a2ea181 SHA-1: eac50c9e66108e2a896cbd2b06c455de57d96ffb SHA-256: 6a21f239b967032bca6a0ff5cd612827f966f11f1ecb4bcf9940a649fad41fd1
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of numerous external links, many hosted on potentially disposable domains, combined with a heuristic for a 'download button' lure, suggests a phishing or malware distribution scheme. The document body is heavily obfuscated, preventing a clear understanding of its specific content, but the overall structure points to a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://kakakmanis.com/contents/files/1751558329.pdf In PDF document text
    • http://thailaundry.com/imgUpload/files/mogorerapuju.pdfIn PDF document text
    • https://www.andreivieru.com/ckfinder/userfiles/files/49872287613.pdfIn PDF document text
    • https://netiko.fr/img/Data/file/xiwekafaman.pdfIn PDF document text
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d5dbe174ca---57069878385.pdfIn PDF document text
    • http://hexindechem.com/upload/files/wovesajevigirijope.pdfIn PDF document text
    • https://alstar.uz/images/shared/file/lezurolixigesej.pdfIn PDF document text
    • http://nhatminhtrading.vn/app/webroot/uploads/files/muwawetaratawisudexonaki.pdfIn PDF document text
    • https://masterjobintl.com/ckfinder/userfiles/files/wotovulujefefomuxaxekozo.pdfIn PDF document text
    • https://coaching-jk-academic.com/ckfinder/userfiles/files/77319494979.pdfIn PDF document text
    • http://musicandyouapp.com/webupload/editorimg/files/disazakedenoxowizewaxalap.pdfIn PDF document text
    • https://soportedevida.mx/ckfinder/userfiles/files/35922103555.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134733a80073---bikobisinipig.pdfIn PDF document text
    • http://lifecare4all.com/upload/files/81844435679.pdfIn PDF document text
    • http://sartoriaventurini.com/userfiles/files/74515841516.pdfIn PDF document text
    • http://abwplazaview.com/uploads/files/4751047460.pdfIn PDF document text
    • http://studioschicchi.eu/userfiles/files/62560598197.pdfIn PDF document text
    • http://tachikawa-derma.biz/ckfinder/userfiles/files/zagizizomijubamifirex.pdfIn PDF document text
    • http://dreamsurgerycn.com/ckupload/files/zafiw.pdfIn PDF document text
    • http://centronegozi.com/public/78378258506.pdfIn PDF document text
    • http://9jamail.com/FCKeditor/editor/filemanager/connectors/userfiles/file/67838959173.pdfIn PDF document text
    • https://zoorichi.com/temp/fckeditor/file/58164385369.pdfIn PDF document text
    • http://wimborst-ceramics.nl/public/view/upload/fckeditor_images/file/rupusi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=plants+vs+zombies+mobile+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_off0000deb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEB4 10660 bytes
SHA-256: 7afda6a5834668d3d5e29600c5cd0a3b6e80e6f7b83a9ae231d51609d9d16e97
font_01_sfnt_off0000f732.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF732 18176 bytes
SHA-256: 57ecc2dbc848cf77cef6dbf1d79ac2ace1f736c4fdad39657bb0f9cdb5b1ada1
font_02_sfnt_off0001258c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1258C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1