Malicious PDF — malware analysis report

Static analysis result for SHA-256 f978903de2274f92…

MALICIOUS

PDF

76.0 KB Created: 2021-06-20 21:00:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: 66d60c9badb613b59c1971c51c4ffb71 SHA-1: 38648176d4a7a9dba037a3da64802680477e5c45 SHA-256: f978903de2274f920e7c43d478ca0339aff0607f004b68f01ee1ba81a0348268
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 a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute malware or phish for credentials. The document body, though heavily obfuscated, contains references to 'Spanish homework solver' and 'wkhtmltopdf', indicating a lure to disguise the malicious intent. The presence of multiple external URIs and link farms strongly suggests a distribution mechanism for further malicious content.

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 http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b7b8f454d95---lofagexovutewawiruvopupi.pdf In PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160829a84083e8---lajonuxemasigemubul.pdfIn PDF document text
    • https://vieclamhanoi247.com/upload/files/vufazaluxewolewoza.pdfIn PDF document text
    • https://ceccarbotosani.ro/userfiles/file/70542266110.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/1607c4de8205b0---bupumanolipiz.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210602194203377.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fef60483cc---83704098379.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/d12fdc3d1e661f766c1d90be6b832ebf/77819331252.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608fd4e722fab---niforumotoxipaboxixuwage.pdfIn PDF document text
    • https://jetaime-shop.com/files/zuxemikunajix.pdfIn PDF document text
    • https://www.travelticket.com.au/wp-content/plugins/super-forms/uploads/php/files/kp3dnvfbnaokovgrasfmc5fl5g/bogutexevun.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/a2d2090f7e47cba8c9ffae4f467826e7/13414553666.pdfIn PDF document text
    • https://szaniterplaza.hu/ckfinder/userfiles/files/novamobutovexasukoxeveri.pdfIn PDF document text
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/41912056bd496dfbd3c9f44ef033b665/kuriwigepe.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=spanish+homework+solverPDF 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_off0000df21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF21 5084 bytes
SHA-256: cbf473a24ce9f3c9ed515d0c49d57bc6704e3293acc47a993f2234470ee22e6d
font_01_sfnt_off0000f02f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF02F 10396 bytes
SHA-256: 88602e1d9363ad32416673998620336fcb4f352430295c47c05baca1c45d0f0d
font_02_sfnt_off000113c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113C6 4324 bytes
SHA-256: 1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e