Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a6ccc2b37ba6545…

MALICIOUS

PDF

79.2 KB Created: 2021-06-12 13:38:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: cc121f634bc033e0419954236fcbfadd SHA-1: 10411421ed05673eb8438d37a5725bcb6aebb552 SHA-256: 7a6ccc2b37ba6545c056f3f468a91174fe583f0f15b4321279884851b1ccef07
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 it is a phishing or trojan delivery mechanism. The document contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the heuristic findings of PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM strongly suggest the document's purpose is to facilitate the download of a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://krisoc.ru/uplcv?utm_term=active+and+passive+voice+practice+test+pdf PDF link annotation
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/599e3c25d3027a951aba19ca557760a1/2857549497.pdfIn PDF document text
    • https://www.propertyfilevault.com/wp-content/plugins/super-forms/uploads/php/files/5a547563172591e20c2be15f3dd1edfd/42927938356.pdfIn PDF document text
    • http://billsky.ee/files/file/jumun.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd4cda83cb4---56256792124.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16080db64b232b---56348630096.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16077b695e7ee2---pilapod.pdfIn PDF document text
    • http://videoacceso.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4c9a926096---godele.pdfIn PDF document text
    • http://aire-limpio.com/img/editor/file/24252343162.pdfIn PDF document text
    • https://www.avenueroadadvertising.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087eafb156dc---ganixakotuxajotowozude.pdfIn PDF document text
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/290255fa1a69011ca7aeb74cc89e1b8c/29528086698.pdfIn PDF document text
    • http://toyotarent.kr/FileData/ckfinder/files/20210612_1953ABB0F3B27A9C.pdfIn PDF document text
    • http://jonkmp.nl/img/cms/file/31201932191.pdfIn PDF document text
    • http://dalnoboy.org/data/filestorage/upload/files/81307822176.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16087495edd023---nexivi.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/5620dbac04ff32d5ea35464562ad1bf4/52202713809.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_off0000f8fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8FD 5168 bytes
SHA-256: 2f70f691f6eb86ce9c7e57354beef6f947989056de35150132e0da0c160084de
font_01_sfnt_off00010aa9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AA9 10792 bytes
SHA-256: ca568ce95c2029ca6c82ce829a98e0876f65b23b191d91694adb48c5f15b3fb1