Malicious PDF — malware analysis report

Static analysis result for SHA-256 6566406a767d3b44…

MALICIOUS

PDF

72.2 KB Created: 2021-06-08 23:08:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: 251312b9fe46c804f9a9f12c88785c5d SHA-1: ac8dc2817794b8aeb06a2926bf7b450cf8650e07 SHA-256: 6566406a767d3b4471d75ed6425ee7d895496621078005c67077935334630082
176 Risk Score

Malware Insights

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

This PDF document is identified as malicious by multiple heuristics and a machine learning classifier, specifically flagged as a phishing trojan. It functions as a link farm, directing users to download software via URLs hosted on compromised WordPress sites and other domains. The embedded content, though heavily obfuscated, suggests an intent to deceive users into downloading a payload under the guise of a text scanner.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://synerhu.ru/uplcv?utm_term=download+ocr+text+scanner PDF link annotation
    • http://www.aluvascientific.com/UserFiles/file/80308889417.pdfIn PDF document text
    • http://jointrilogy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b535c07057---tebif.pdfIn PDF document text
    • https://www.proctoloji.com/wp-content/plugins/formcraft/file-upload/server/content/files/160779727a0053---24316738848.pdfIn PDF document text
    • http://interiorconsignments.com/media/file/90448974202.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/l1icuda3j6bhvg7hb9tl5rgm62/59266542062.pdfIn PDF document text
    • http://stlnsk.ru/uploads/file/43557790317.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/siodpdf9vej4uudjkdvi88mpk7/74420652519.pdfIn PDF document text
    • http://divorce-difficile.fr/userfiles/file/99039682340.pdfIn PDF document text
    • http://vorne-sitzen.eu/pcms/content/file/pibenusebifebafajufo.pdfIn PDF document text
    • http://aaaexpressac.com/userfiles/file/wegele.pdfIn PDF document text
    • https://www.hed-endo.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160b5d4b6cc85a---76092692610.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1609ca74211ce2---83165545999.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160783723b60b5---73766031793.pdfIn PDF document text
    • http://aptchasers.com/FCKeditor/userfiles/file/68872311886.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8e89ca61c---38537033512.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_off0000dc31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC31 5092 bytes
SHA-256: 3213084a2196cdec6f28b42fd1c0ea94d867c977ce3ca9adb3ec22c0f2dd94df
font_01_sfnt_off0000edb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB0 10896 bytes
SHA-256: d108277faff5782cc3ab71d39972fbaf3e12f8b01ba61cf47cb271d45db5548a