Malicious PDF — malware analysis report

Static analysis result for SHA-256 98f4c0c5cdbc6fec…

MALICIOUS

PDF

68.8 KB Created: 2021-04-30 07:22:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 373e359dce78651c0157d3d1a8d1977f SHA-1: 24b8eae3d6c5acb40cdad7cac07b4156b6c57df4 SHA-256: 98f4c0c5cdbc6fec43455e0fb6c48dcebc4ac7b3abde9effc940fb46d2e40eeb
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. It functions as a link farm, directing users to numerous compromised WordPress upload directories and other potentially malicious sites. The presence of multiple external URIs and link farm indicators suggests an attempt to redirect users to phishing or malware-hosting pages.

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://alibabashipping.com/userfiles/file/11672089798.pdf
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607093915c5b8---sagul.pdf
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/ad79ab53242782351c5b0117adefddcb/zojukozanozisa.pdf
    • https://bellevuecommunityfoodbank.org/wp-content/plugins/super-forms/uploads/php/files/725b5cb64cd5305b9c7890ed9c10be33/20964442153.pdf
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1608afbea06ce1---boderufofagenixixa.pdf
    • https://tlpnw.com/wp-content/plugins/super-forms/uploads/php/files/3cf67323ad63be48b24772df362666bf/3853747266.pdf
    • https://robotics-institute.com/wp-content/plugins/super-forms/uploads/php/files/635gpav81iggqmltv5od3u35fe/71794619526.pdf
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/216ea8447f69ce139b8f2dbe51980cc7/zofuwowepofivugijod.pdf
    • http://www.gunyagder.org.tr/wp-content/plugins/super-forms/uploads/php/files/1hqf82noqlegderegdpj862u22/wotafa.pdf
    • https://www.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607f51680172e---45417235611.pdf
    • https://nobleanimalsanctuary.org/wp-content/plugins/super-forms/uploads/php/files/tmp/wovesuziliziba.pdf
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/7f2043fa4d141367532bc7269fda7b16/gupirefuroja.pdf
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/b343bb1a91f3216842a1f4f0bc2be6cc/kekud.pdf
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/160762068d1fc2---gupevu.pdf
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/77f211ac27a6098f8cba5d5fe69cd700/ditabixa.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=duck+hunter+games+free
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d237.bin
b2fb02f105ef633e4298996d944fa6d295f4e02c07bd3170956d115c935a99f5
pdf-font-stream PDF embedded font (sfnt) at offset 0xD237 5324 bytes
font_01_sfnt_off0000e438.bin
7bcfe8ef1c052528b11a2892f83dbf61967c87ed630a100325dda113a6f7c1d2
pdf-font-stream PDF embedded font (sfnt) at offset 0xE438 10028 bytes