Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf6bfc628e8accc3…

MALICIOUS

PDF

74.3 KB Created: 2021-06-14 09:42:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 4e1b60c6995cd77096d08daf8d3859ce SHA-1: ae460c2daf3710e6e707b169320c233a70f130f2 SHA-256: cf6bfc628e8accc309c968c08a23f6bffb5a76702421059ff74c69721343d1b6
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress sites and potentially malicious URLs. The presence of embedded URLs and the nature of the heuristics suggest this document is designed to redirect users to phishing or malware-hosting sites.

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://ketchas.ru/uplcv?utm_term=colour+bomb+candy+crush PDF link annotation
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/160a553588f0a5---vevoxefuvemomitudegepe.pdfIn PDF document text
    • https://brandonsmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/vtv3dkivu8hf2rua1ehiuohgt2/48971097417.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/c02579996230c4dfa1d79a6a8dd9c196/74772045883.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b80f4cd007e---sudifenere.pdfIn PDF document text
    • https://interesttour.com/wp-content/plugins/super-forms/uploads/php/files/b37c9c058e503edd442f3cbdf12798aa/xorusimewojatojo.pdfIn PDF document text
    • http://airconbank.com/upload/fckeditor/file/37765676501.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/16074b48409399---gifixevinav.pdfIn PDF document text
    • http://beautybybelief.com/admin/images/file/tobob.pdfIn PDF document text
    • http://baschin-heizung.com/meineBilderAlbertGrundschule/file/pawalikuzajobege.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f44a60b689---4632706978.pdfIn PDF document text
    • https://etimes.mn/uploads/files/76310819854.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609a7887dcb02---34965089497.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/ttjsjvon0jkng0fu9moh4hq7i2/rutulomipomab.pdfIn PDF document text
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/9135069a92befd29db90b76a1e218d9c/48663894676.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/160786646dd016---bedorur.pdfIn PDF document text
    • http://steelbo.com/uploads/admins/u0/files/20210611165734.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_off0000e53f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE53F 5324 bytes
SHA-256: d0bcda6b69569668d112347b2a66c6bfdc207f41d437f9642bbcf5bbd355aa5f
font_01_sfnt_off0000f728.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF728 10760 bytes
SHA-256: 51a7511e6f7452b7af1769c88dbbe868c8fa7fe95de2c83b45ac655ce8963172