Malicious PDF — malware analysis report

Static analysis result for SHA-256 a93bddb3b8c3121b…

MALICIOUS

PDF

99.4 KB Created: 2021-06-22 16:23:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: d70219144c13ba9fab5d5632f4c3c9d2 SHA-1: 8b56d94c6a30187bf2402204fa5876c219c8340a SHA-256: a93bddb3b8c3121b95d4dc1e85d1fecc200190ab5b2943ec25fd063824e2861d
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to compromised WordPress sites and other disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, appears to contain metadata related to a manual, likely a lure to disguise the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://vinhthuan.com/upload/files/xugobilaredukesake.pdf In PDF document text
    • http://dermaktif.com/imgup/file/38979182807.pdfIn PDF document text
    • https://alfa-pechati.ru/wp-content/plugins/super-forms/uploads/php/files/1ae5563991df3d930d5d3a60f7031c64/34401535096.pdfIn PDF document text
    • https://www.nosolodespedidas.es/wp-content/plugins/formcraft/file-upload/server/content/files/160874c1872862---65716452336.pdfIn PDF document text
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/87deae596ff0b23857b35d8a26108f9e/32650935224.pdfIn PDF document text
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/8l66dqj4f4r1tnqrug7kvmemrp/sefuvexobamatizomi.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/1607fa3f22276a---wetojaxopevapejuk.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/160752cfd964ce---81100387626.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-5-14/20210514180028721663.pdfIn PDF document text
    • http://archi1919.com/smlclub-files/file/wajubogigo.pdfIn PDF document text
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/819b9d98b5e7d4ba8d2ff966882c537c/68181070184.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160793ce59f3ef---xidobopuporavejula.pdfIn PDF document text
    • https://108pizza.pl/uploads/userfiles/files/zamokebejifaxo.pdfIn PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16076eac550dd6---13178862058.pdfIn PDF document text
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/a529b0ee8340f8f9801e0f9d8d88f20e/38816723312.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/c1c9051ce2bd02324a05d8805c892905/70696291867.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=cytoflex+lx+manualPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eb38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB38 29844 bytes
SHA-256: f4620bea2acc271e3d1fd77ee841ed3dba0ab01911fef02986c2c9661bbeee91
font_01_sfnt_off000148fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x148FD 4712 bytes
SHA-256: 28e0b71e09bb676810217a421980c179be140b7762fdd454fa1c627a41ba1efb
font_02_sfnt_off00015900.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15900 11524 bytes
SHA-256: 20b4ecae782c701d002809b511422a645103a9712c779f7da541531a9a9a0d82