Malicious PDF — malware analysis report

Static analysis result for SHA-256 c783007e3cae21f7…

MALICIOUS

PDF

77.1 KB Created: 2021-09-11 20:19:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 3aeadfb6089ad7b5b1537bda843daed5 SHA-1: 8eec82af6c0fb15c887b23b9541e841e2dbe6a34 SHA-256: c783007e3cae21f78bf4ec3748a94091eb391ed2bb7291c2ebf68313447893c0
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to various websites. Several of these URLs are hosted on compromised CMS platforms or disposable domains, suggesting an attempt to distribute malicious content or conduct phishing operations. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports the assessment of a link farm designed for potentially harmful purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://greenline.bg/userfiles/file/bupunugomasununu.pdf In PDF document text
    • https://www.highettmetal.com.au/application/third_party/ckfinder/userfiles/files/20945118585.pdfIn PDF document text
    • http://www.protectakoteasia.com/ckfinder/userfiles/files/32938724055.pdfIn PDF document text
    • https://hssanesteban.cl/files/mosuwubi.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/3e9peg7ov9t760lc9jab077i93/41703794996.pdfIn PDF document text
    • https://snoman.mb.ca/ckfinder/userfiles/files/vopuvukemi.pdfIn PDF document text
    • http://barrospizzadb.com/uploads/files/kudulunolaxa.pdfIn PDF document text
    • https://marblobathware.ph/app/webroot/img/files/75718252145.pdfIn PDF document text
    • http://lechioutdoor.com/userfiles/file/41747843954.pdfIn PDF document text
    • http://mnwebdesign.dk/userfiles/file/gelinavimubirepubirop.pdfIn PDF document text
    • https://vientangluc.com/upload/files/rugomubumep.pdfIn PDF document text
    • http://www.fuchingrading.com/upload/file/42631719358.pdfIn PDF document text
    • http://www.egymast-segito.hu/uploaded/fck/file/tipopafenejade.pdfIn PDF document text
    • http://daiichibus.vn/uploads/news_file/78397255237.pdfIn PDF document text
    • http://bobiniauto.com/userfiles/file/gaxulitezemo.pdfIn PDF document text
    • https://dmshospital.com/mm_engg/files/bekolukijuviwiw.pdfIn PDF document text
    • https://ourcampuswindow.com/ckfinder/userfiles/files/67991762318.pdfIn PDF document text
    • http://como.gattinonimondodivacanze.it/themes/userfiles/files/63583195607.pdfIn PDF document text
    • https://realxenon.ru/uploads/files/tixobu.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16134e6987a458---11768740234.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612fe0df937b7---doredisowokusinu.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/a5b9cc2e754e67d059fa96475f5c071c/kakewiwo.pdfIn PDF document text
    • https://obermeyer-modemarkt.de/upload/file/wokezofubojufabus.pdfIn PDF document text
    • https://heureka-cz.eu/files/76376014521.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16133ddb60b1bc---zukadiwonufejevimug.pdfIn PDF document text
    • http://patanamachine.com/imgUpload/files/8280667177.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=hexadecimal+number+to+binaryPDF 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c792.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC792 10812 bytes
SHA-256: 6c789f44208a7a4d1a97091f7b8b266eae14f1a6068ef5ad2fa45cb93ba32302
font_01_sfnt_off0000e061.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE061 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f873.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF873 17732 bytes
SHA-256: cd11cf90da7ecece17bb83ff562ffc3cf7f4b3d7c829d677c773ddc3b0ebb966