Malicious PDF — malware analysis report

Static analysis result for SHA-256 fcf57da0f5fffec2…

MALICIOUS

PDF

73.8 KB Created: 2021-06-09 01:00:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 9562dc261b10b6eec32017113b2323a3 SHA-1: 31dbb9187de99600a8195f2e23aa0d7b03ba9716 SHA-256: fcf57da0f5fffec2d2b74237863eaf7f3ea2cdc2a14b4d8634ccfad283b8ec85
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1204.002 Malicious Link

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories, presents a deceptive download button and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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.
  • 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://synerhu.ru/uplcv?utm_term=gta+v+ppsspp+link PDF link annotation
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/160affb14bd48b---14108037111.pdfIn PDF document text
    • http://texmet.pl/userimages/file/65673793280.pdfIn PDF document text
    • http://tavernadelsnoguers.com/wp-content/plugins/super-forms/uploads/php/files/3c7d7ef730957205d95af77e441c449b/buxadoku.pdfIn PDF document text
    • http://www.aadhar-interior.com/userfiles/file/nizekorif.pdfIn PDF document text
    • https://a2designbg.com/userfiles/file/4674534075.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076b2563dc33---buropidogujijikatuk.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/9ffbf0e424907030f8b46c330f65bca9/78813889191.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072665dc74e4---suburumijojujazuneri.pdfIn PDF document text
    • http://edgecs.net/documents/2206602296.pdfIn PDF document text
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/8dba2f6d742b37a87ad3db45e9c4560c/88229634853.pdfIn PDF document text
    • https://makemycake.gr/wp-content/plugins/super-forms/uploads/php/files/qgee7nstr551dtbstu7hejeada/59677997419.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/905fbae9d773d5f865e4e44f3fc2923d/jezimepabig.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/afb41ff59c705ca8302e126393e9593d/lalitejikovode.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b29f6333ee8---sikikovujunawoka.pdfIn PDF document text
    • https://sfasg.jp/js/ckfinder/userfiles/files/dubizu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e478.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE478 4872 bytes
SHA-256: 1b0c55e7e326b7ebec32870fd15f70678268c3824d24d741f03b808350b9cefd
font_01_sfnt_off0000f52d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF52D 11532 bytes
SHA-256: 2d033be1cb6cbbee680364f007978816c5314ab0ff1edb2c2c86d3d476ef6fd5