Malicious PDF — malware analysis report

Static analysis result for SHA-256 3722a5b22ae08a09…

MALICIOUS

PDF

84.7 KB Created: 2021-09-13 01:24:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8f5a57ab09631f84de335d70a5842914 SHA-1: 2310eab3fbe69f535aba3ef5aeb084ee6225efce SHA-256: 3722a5b22ae08a09d7672df2a54926f4e5f6df1d42e8191ed4299c54efd767b1
126 Risk Score

Malware Insights

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

The sample was flagged by multiple heuristics, including ClamAV and an ML classifier, as malicious. It contains a large number of embedded URLs, many of which point to disposable domains, suggesting a phishing or malware distribution campaign. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating the PDF is designed as a link farm.

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 https://medvor.ru/uplcv?utm_term=acelerador+de+tempo+para+jogos+android PDF link annotation
    • http://maychamsocda.vn/images/userfiles/file/29780414608.pdfIn PDF document text
    • http://rockhousemethod.com/ckfinder/userfiles/files/dizekuj.pdfIn PDF document text
    • http://goodfortune.hk/UpLoadFile/file///lumiwavozuw.pdfIn PDF document text
    • https://sinaia-vik.com/admin/fckeditor/editor/filemanager/connectors/php/file/wimogudebatije.pdfIn PDF document text
    • http://dawahcity.com/userfiles/file/94651531739.pdfIn PDF document text
    • http://upakuika.com/img/file/dinaxodivumuvuniwigu.pdfIn PDF document text
    • http://thepducphat.com/upload/files/lezotofuletotinuresutoz.pdfIn PDF document text
    • http://asclyziarskyklub.sk/userfiles/file/80956324262.pdfIn PDF document text
    • https://rallstarawards.us/nbloom/fckuploads/file/zuwowo.pdfIn PDF document text
    • http://waetsukai.jp/system/ckfinder/userfiles/files/livofen.pdfIn PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161338c52e91cd---migulamewulaluwebebojawuv.pdfIn PDF document text
    • http://besteva.com/upload/files/92461371252.pdfIn PDF document text
    • https://www.nhabe.com.vn/ckfinder/userfiles/files/27431550456.pdfIn PDF document text
    • http://ilonew.tasksplan.com/ckfinder/userfiles/files/rowedajisixenutifenuzajuz.pdfIn PDF document text
    • http://gps-ambroisie.com/ressource/site-image/files/32062419488.pdfIn PDF document text
    • http://partnercable.com/files/66920827015.pdfIn PDF document text
    • https://globalcareerclub.com/FCKeditor/userfiles/file/guwimepufuzufasub.pdfIn PDF document text
    • http://apnschool.in/singhania/downloads/file/vegilibewelebajefinazim.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/16136bcfb876f7---pitogapuwifeparakotu.pdfIn PDF document text
    • http://jiab.net/userData/board/file/84486054889.pdfIn PDF document text
    • http://blossomtour.net/FileData/ckfinder/files/20210912_2BBD190171250AC2.pdfIn PDF document text
    • http://www.videocopilot.net/assets/public/ckfinder/userfiles/files/38278293184.pdfIn PDF document text
    • https://alienaquatics.com/home/gb/public_html/ckfinder/userfiles/files/dubuzenejemeguwi.pdfIn PDF document text
    • https://oxi-dental.ro/imagini_ws/63446229879.pdfIn PDF document text
    • http://lawyermo.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/38804232322.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_off0000de49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE49 10968 bytes
SHA-256: 8bacaf121079f80d478413b336f1eb2a6512095b1fe81f7104aa46397c94d1a7
font_01_sfnt_off0000f781.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF781 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F93 21016 bytes
SHA-256: d1f68c6c3d211227d59c0de9483b822c812a4255d998ba7873a8d99f27455571