Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3f93d258d305a4a…

MALICIOUS

PDF

103.5 KB Created: 2021-09-15 03:07:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3d39c82baa7409b3eafa47221ad40d45 SHA-1: 819b018214c972ac123bae318b750c86de616a68 SHA-256: c3f93d258d305a4a6103ab68f7e4307e3e96d719b9b62c03fe7f73b068343de6
174 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external URIs pointing to disposable hosting, indicative of a link farm used for phishing or malware distribution. The heuristic 'SE_PASSWORD_ARCHIVE_LURE' suggests a common tactic of providing password instructions to bypass gateway scanning, further supporting a malicious intent. ClamAV detection confirms the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://coretry.ru/uplcv?utm_term=square+root+of+216+simplified PDF link annotation
    • http://iucecb.com/files/file/dogiwi.pdfIn PDF document text
    • http://ctyrkolky-gamax.cz/data/dokumenty/42198047548.pdfIn PDF document text
    • http://worldofpacifiers.com/editor_uploads/system/files/taxadolafaxanipaxo.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614112cca53cc---13156383902.pdfIn PDF document text
    • https://haysalon.com/public_html/userfiles/file/3401411755.pdfIn PDF document text
    • http://chinahongji.com/d/files/41588741057.pdfIn PDF document text
    • http://triple-a.co.th/ckfinder/userfiles/files/14869057500.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/mt93vk1lu5ja47tujhin3ks9o6/fezinogefulol.pdfIn PDF document text
    • http://iranjobex.com/cache/fck_files/file/degigeduguxiresegiwefo.pdfIn PDF document text
    • http://michael-dhom.com/webseiten/file/loxoxizumezatepez.pdfIn PDF document text
    • http://safaraval.com/basefile/safaravalcom/files/46254254584.pdfIn PDF document text
    • http://xn--80akoseq9f.xn--p1ai/userfiles/file/jitufexinijirefipe.pdfIn PDF document text
    • https://genegurumiraclehealer.com/userfiles/file/vubekenafef.pdfIn PDF document text
    • http://graylegalservices.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/20083931981.pdfIn PDF document text
    • https://www.scmsgroup.org/ckfinder/userfiles/files/belanedo.pdfIn PDF document text
    • http://www.slenderclub.cz/ckfinder/userfiles/files/84992229348.pdfIn PDF document text
    • https://i-chat.tw/js/ckfinder/userfiles/files/58066131012.pdfIn PDF document text
    • http://shendaoguoji.com/data/attachment/file/tokebaperu.pdfIn PDF document text
    • https://rent-1.es/ckfinder/userfiles/files/dopituxesa.pdfIn PDF document text
    • https://cnn-logistics.com/asset/files/35587368829.pdfIn PDF document text
    • https://www.sonorisation-auxerre.fr/ckfinder/userfiles/files/12182271190.pdfIn PDF document text
    • https://hondamienbac.vn/userfiles/file/8924806048.pdfIn PDF document text
    • http://budka39.ru/files/jirotujasamepufale.pdfIn PDF document text
    • http://gayaarchi.com/userfiles/file/20210912030038.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_off00012a10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A10 11216 bytes
SHA-256: 19e2c611427bab8be33e54dff16463a924726204b288bc4e9bd71fdd13a58eed
font_01_sfnt_off0001443e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1443E 19996 bytes
SHA-256: 090c8cd3b1d3a53a726f0dd32b8d8ebd51078e58942ba32688bfaba3ae665c1f
font_02_sfnt_off00017825.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17825 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1