Malicious PDF — malware analysis report

Static analysis result for SHA-256 31221340ed882e36…

MALICIOUS

PDF

72.8 KB Created: 2021-06-23 08:22:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: 5d5d297c9acf8e900744aa9c1b0ed2cd SHA-1: 9f05fccf77eda3c2cc5bb6cbeb6d266bc6b6850c SHA-256: 31221340ed882e365d08725f8f3bcb1b1eba99d32ede19fe73bbe663556274fe
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

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://arerp.kr/data/file/%5C/kosowupixabepajuz.pdf In PDF document text
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607836a4a18b9---90466793315.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160a5683e7d527---xuwegajufalepodavogawi.pdfIn PDF document text
    • http://aliceinformaticasrl.com/user/pages/zefisewawoxejamujijexi.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160d21f88a96ab---mobitujogi.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609c82ef24996---pipotezebitajowaxepebiruv.pdfIn PDF document text
    • http://xn--80ab1a9a.xn--p1ai/sadm_files/45489945514.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/db958bf6aa444f8c5e5202cb3c2ffffd/74128205422.pdfIn PDF document text
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc312818ea---jazitivifupetibotes.pdfIn PDF document text
    • https://hr-serdahel.hu/images/file/zanabawiribunilebi.pdfIn PDF document text
    • http://riskhedgetech.com/uploaded/file/385671440609b6edf13d02.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608785a30fc25---3069081346.pdfIn PDF document text
    • https://rosemonttherapy.health/wp-content/plugins/super-forms/uploads/php/files/9t2d3o6su1qfk1uvtvtv0271n6/xejologisoduzuw.pdfIn PDF document text
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/ed304faab0580b47cbc82fb59a788b7d/donatanilaxipulewetupe.pdfIn PDF document text
    • https://ilc.ua/wp-content/plugins/super-forms/uploads/php/files/varqfiiaka5ireqf0n0jn540n6/68224518970.pdfIn PDF document text
    • https://mmszke.hu/files/file/3750459646.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=pdf+to+excel+extensionPDF link annotation
    • 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_off0000e2e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2E8 4780 bytes
SHA-256: 39394829479ad4aace4c27f3060d348c4742650776b1c775529b8f81cb81aa30
font_01_sfnt_off0000f34c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF34C 10180 bytes
SHA-256: 19e05c5ca230f7c0b09b86d03f24e75cdeee7d9d6e98173918926cdd28ec8aff