Malicious PDF — malware analysis report

Static analysis result for SHA-256 a66e91752015cd74…

MALICIOUS

PDF

67.1 KB Created: 2021-06-08 12:51:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: c7975c570ac4abe5b0862efef4efd6f7 SHA-1: 04ef6c445749d66a7fe993023c50981fc79857c7 SHA-256: a66e91752015cd74dee3b4d836a21ae68d71f8fa3f0f230073a75b45f4964ce1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs and links to compromised CMS upload storage, suggesting it functions as a lure to external malicious sites. The PDF structure and embedded links point towards a phishing or malware distribution campaign.

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://huntic.ru/uplcv?utm_term=dante%2527s+inferno+levels+of+heaven PDF link annotation
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/a3d72b8de0c878dd0f1dd6408c630f4b/wotixipe.pdfIn PDF document text
    • https://www.penyembuhanholistikreiki.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075a952cddef---sulofopud.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/160a8ffe7154c2---vavelibosud.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a53e7e2b49a---wotidosoxukisepomubob.pdfIn PDF document text
    • http://pvsystexperts.com/wp-content/plugins/super-forms/uploads/php/files/pr6hha42lv2dfqhrh3gs94o960/vesosijofatuwevufemojabit.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071a8e795c66---86636981114.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/1h34jmli9kg8uhr2mpeoieuaoi/nurigazurofobejimemor.pdfIn PDF document text
    • https://kogan-photo.ru/wp-content/plugins/super-forms/uploads/php/files/081540b062b2aded9e30bea27c5e490f/53265117964.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/7eb07417ad2de686bae28f38cfe1250f/vuxozigajasal.pdfIn PDF document text
    • http://allamericannursing.com/userfiles/file/6797425313.pdfIn PDF document text
    • http://alliance-ltd.com/userfiles/66185690064.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/rtainbq8ooclkd60p8m4bnqb9k/tuwutawagijej.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080b0b3ebd04---20660952890.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/r71ilojonlf8mt9naiq0qfi8i6/tovoxotulovulu.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_off0000cd45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD45 4948 bytes
SHA-256: f7fa87a9f32b57f2bd7aa4f1de38ae775ff582939ffb1d58d5bf7ef4f5dd8377
font_01_sfnt_off0000de26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE26 10056 bytes
SHA-256: 5f5131f3e1431ae8438823a3c1b9f6f78f73517cb74d6ee87a6caf8594fba1f7