Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b6618290a57fc42…

MALICIOUS

PDF

81.8 KB Created: 2021-08-24 18:41:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 3a21c4ca821f25de7c2d1a3f07ed9376 SHA-1: 1ea23915b81be8260088576067823141082ced3d SHA-256: 9b6618290a57fc42c1a3db0f2700249fc5b498b5bfee477ebe6ec48b0b3bc4c4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm pointing to numerous websites, many hosted on disposable domains or compromised CMS uploads, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The document body is unreadable, but the heuristic firings and URL analysis confirm the nature of the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://jatyn.cn/upfiles/202107/file/1625883194.pdf In PDF document text
    • https://40parables.com/wp-content/plugins/super-forms/uploads/php/files/9c35aa50b95db3e4f7142fb750b1e5cf/49219828490.pdfIn PDF document text
    • https://wonkingchina.com/d/files/notaton.pdfIn PDF document text
    • https://cakenepal.com/userfiles/file/tupotapoxeko.pdfIn PDF document text
    • http://trlgpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/41157985017.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab232d5e1c6---31137461017.pdfIn PDF document text
    • http://firegallery.ru/img/upload/16302165038.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/16079894d75d37---97665815004.pdfIn PDF document text
    • https://jin-hung.com/userfiles/file/6042835168.pdfIn PDF document text
    • http://domgr11.ru/uploads/files/9099507113.pdfIn PDF document text
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f6b0cf2df8a---79455068531.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b35057d7654---winerimasuxod.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/160acb652ee197---vofepodubog.pdfIn PDF document text
    • http://runbo.net/upfiles/files/1629509317832.pdfIn PDF document text
    • http://siciny.pl/userfiles/file/zatatisubowudusiwudafix.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/8162efb25794a02f895f5fc7680416f0/volunoga.pdfIn PDF document text
    • http://gelateriacool.it/userfiles/files/wisewidujirojid.pdfIn PDF document text
    • https://shinyjewellers.com/wp-content/plugins/super-forms/uploads/php/files/8b5n7ccd171bjo6requid16c2h/ledewisok.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/0648b833df12c3059f3eadda17d6e028/tomuxibimubitutopazawo.pdfIn PDF document text
    • http://garmagostaran.com/Upload/file/baxozitogigopolifufo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=directions+to+atlantic+city+new+jerseyPDF 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_off0000db69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB69 10556 bytes
SHA-256: 869ecac4423600390f321faab37a3842debd76479209ed3542ddd5b000a18fa2
font_01_sfnt_off0000f3a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3A5 17464 bytes
SHA-256: 14561b33e3a1d5e0bcad0c90fef6572abb2462cd2938404d0dd67ba58e5ebff9
font_02_sfnt_off00012133.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12133 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1