Malicious PDF — malware analysis report

Static analysis result for SHA-256 44b4a8b45856cf83…

MALICIOUS

PDF

68.3 KB Created: 2021-05-27 14:05:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: b8361a45337653bd52a1510ceb897dfe SHA-1: c5f47d35f1df75dfa689473ed15219f9119816be SHA-256: 44b4a8b45856cf8334f68d8a87564cb08c972e005927056a064dcfb98db35f63
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains a link farm with numerous URLs pointing to compromised WordPress sites and other domains, suggesting an attempt to redirect users to malicious content. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution attempt.

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 https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/05ed1d34faf8992a07a3b9134e119162/79540375504.pdf In PDF document text
    • http://adria-ex.com/images/blog//file/16211497671.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/os4mc6dfglte78te3dqhegh3p3/47542251276.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087fae10cd47---mogotefaso.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8e278ccc58---lexosamufali.pdfIn PDF document text
    • http://poorclarescork.ie/images/zagerimu.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/731ae090e4b7ce105dcf3c64945eba0e/42717696342.pdfIn PDF document text
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/a0389714c486ad8a4a3ef21c21f45218/65578471571.pdfIn PDF document text
    • http://batiment-tunisie.com/userfiles/file/36072543492.pdfIn PDF document text
    • http://xn--clinicaquirogavilario-vbc.com/wp-content/plugins/super-forms/uploads/php/files/rrk75s373o12bkb7cth6petf86/80548894628.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16073a0184730d---50613201422.pdfIn PDF document text
    • https://mkting.com.co/wp-content/plugins/super-forms/uploads/php/files/ae4dfbe831a1c52b5ac18f21a37ee725/13828428821.pdfIn PDF document text
    • http://www.yoko-ono.be/images/userfiles/file/tivakuzitakanamuro.pdfIn PDF document text
    • http://nappsa.org/userfiles/file/sajibixekikonotenusubom.pdfIn PDF document text
    • http://fritz-fahrlaender.ch/download/87802638877.pdfIn PDF document text
    • https://luyenthitoeic.info/userfiles/file/91743880301.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/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=urell+comprimidos+recubiertosPDF 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ca70.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA70 5140 bytes
SHA-256: 921c9e8c464dd3502a7ab84cff3ce7f832aa6abba9e0a57033e4fe251a476e6c
font_01_sfnt_off0000dbd2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBD2 12036 bytes
SHA-256: 9342618c46f546e248f16700c4e2e9337de1f41bffb5f05119bd35e963cfa21d