Malicious PDF — malware analysis report

Static analysis result for SHA-256 cbdb6ec8af90517f…

MALICIOUS

PDF

98.9 KB Created: 2021-06-04 18:42:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 8df1187de02134cf8edc05f040c95eba SHA-1: 36ea78e20de62fece7ba127c04d294a76feb523b SHA-256: cbdb6ec8af90517fc82ab6014a922da15621715857d93982be9f5d678a654507
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. It functions as a link farm, containing numerous URLs pointing to various domains, many of which appear to be compromised WordPress sites or disposable hosting. The embedded URLs suggest an attempt to lure users to external sites, likely for phishing or to download 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://allytemp.ru/uplcv?utm_term=ejercicios+de+matematicas+para+primer+grado+de+secundaria+resueltos PDF link annotation
    • https://soechi.net/userfiles/file/41766577788.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/be5d8c467532b9030a51ac798534b23c/netesimitul.pdfIn PDF document text
    • http://groupkaishan.com/d/files/5252102490.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/tajoworalanifat.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082d7d75dc45---70901949021.pdfIn PDF document text
    • http://rolmech-strzelno.pl/Upload/file/linelunuxuwulijikasetudek.pdfIn PDF document text
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/bce35119c1e87c5697d35b9ff1d63bcc/88901607878.pdfIn PDF document text
    • http://auburn-properties.com/userfiles/files/sowoje.pdfIn PDF document text
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089a494d95b2---padorunurerafe.pdfIn PDF document text
    • https://toskov-yordanov.com/userfiles/file/70903584501.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160af9e718ec11---pozakatolawedukalapifu.pdfIn PDF document text
    • https://www.sacda.org/wp-content/plugins/super-forms/uploads/php/files/dv59a6n65i38miragjka176791/81926918843.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/31f9dd845ba31abff8146e53766d193e/jufit.pdfIn PDF document text
    • http://karthikeyanjayaram.com/userfiles/file/78271716558.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b456602d706---5940441553.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1608c4eab1d4bc---78948985711.pdfIn PDF document text
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072d3d3e9b1e---37468309346.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_off00013f36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F36 5428 bytes
SHA-256: 9892e3ae9b233cf2e8fc9acbaea887948acc82a4e96406e67fc1972cf3107513
font_01_sfnt_off00015198.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15198 12808 bytes
SHA-256: 4b5c49eb6fdb0e1c2f69cc493a98b8e63648e1eabc4cc32ba8cac18dfcb0ad27