Malicious PDF — malware analysis report

Static analysis result for SHA-256 911c4c937b464db6…

MALICIOUS

PDF

72.9 KB Created: 2021-05-28 06:55:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: 06ab2e1fe68d9e28ab8127504c5d018e SHA-1: 38ea5894dff36ba49f7d1e8bd746772bf5b7db86 SHA-256: 911c4c937b464db6bbb1c6674011a8fbd5ef9956f6a564cfa1f191c0bcddfc1f
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, specifically identified as a phishing trojan by ClamAV. The document contains numerous embedded URLs pointing to compromised WordPress sites and other disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of 'utm_term' parameters in some URLs indicates a potential phishing or SEO manipulation campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://irlanc.ru/uplcv?utm_term=yas+profil+resmi PDF link annotation
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1609b84f3dc927---60477605550.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b762ae87a4---30384345979.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16093290589c06---nupewatadopot.pdfIn PDF document text
    • http://meble-tk.pl/userfiles/file/kitesadunorubivolifabunon.pdfIn PDF document text
    • https://repare-ton-smartphone.com/userfiles/file/saxosewaxonagadi.pdfIn PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/16078abe8c95a8---budesivezijesebifokamimat.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/1609b417801fd0---sadibumadegawuro.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/75861aaf714da55a345e8058d1dae443/9166303753.pdfIn PDF document text
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/300f3998684faea17076033cd3af3968/62526410601.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/612c1e0e4ff66395dd3fce1b23d79e2f/12215747785.pdfIn PDF document text
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/38508d0750b47c84f523c0ce0f023071/sakafuxabodalalum.pdfIn PDF document text
    • https://drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606f07673665f---sesataxajovigebetak.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/5aa865dfbeb9026668e8d4caf0526420/94825047618.pdfIn PDF document text
    • https://qamarapps.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081a23b497f2---bemaralorezudatokiniv.pdfIn PDF document text
    • https://grand-forge.ru/wp-content/plugins/super-forms/uploads/php/files/75bf14f6dc0f0eb39387c8e2f79858c2/44084041531.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607b7585ee8d1---rusonemesoj.pdfIn PDF document text
    • http://daoltrading.com/userData/board/file/99544933382.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_off0000dec5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEC5 5008 bytes
SHA-256: 46e9cadc4c3726f507a7764f064408ebcf1dfa920f8f7eb69ba876112fb623ed
font_01_sfnt_off0000efb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFB9 11632 bytes
SHA-256: cd1250b84041d0c022aec17b4a769d58f68d3e5e1c3b9a21cfdadf12d78f6d64