Malicious PDF — malware analysis report

Static analysis result for SHA-256 7df1412ba1d3a5f7…

MALICIOUS

PDF

71.7 KB Created: 2021-06-14 02:35:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 65203ee42e0613fd22f9bb7033663e11 SHA-1: 635d347f531af6d39cbb6dc08320ada8a7f1e74a SHA-256: 7df1412ba1d3a5f7720c03189f16e1b972787cf214c9c957cf2dd2ebb9a3a4d6
156 Risk Score

Malware Insights

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

This PDF document is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It functions as a link farm, directing users to various URLs, some hosted on compromised CMS platforms, under the guise of search results for a popular textbook. The embedded URLs likely serve to download and execute further malicious content.

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 https://smidgel.ru/uplcv?utm_term=cell+biology+bruce+alberts+pdf PDF link annotation
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/9efaf44daba75edf9056410f16383e68/jekozesaze.pdfIn PDF document text
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160767756d29e6---24742232941.pdfIn PDF document text
    • https://alianzatours.com/imagenes/file/sotabujularaxodun.pdfIn PDF document text
    • http://www.studiolegalefusimorelli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbbda4e8dff---3973393458.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/o6h0ag4dtvq45hu2jphatgrkub/wunizodezedaseliju.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf57a1ce9f---xadizaxuxa.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160bbb908d6161---sudiluwozuru.pdfIn PDF document text
    • http://allaboutdowney.com/userimages/47544254944.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ac26bb21f0523d972e9ce9d809492717/lufirux.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1608ea3bdd540e---95814236689.pdfIn PDF document text
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/9bc1d53c6f2bc18781ecf3c58f022a44/47837896081.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a47965909a0---novaja.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b767a7586a1---xaniz.pdfIn PDF document text
    • https://weblative.com/wp-content/plugins/super-forms/uploads/php/files/7lmmmcb0hd6j9ib4v4mea180lo/wonomilosoxaworoje.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_off0000da60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA60 5472 bytes
SHA-256: 533dc186fde24aee7964decd7e977340b20245e7093441d9afb5677ac5eaddd1
font_01_sfnt_off0000ed0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED0D 10920 bytes
SHA-256: 2db63c30f8cb3077b31306d05ac60ed6dcdbd4baf656a6e551a997b0524defea