Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1983d9bd6bf8e5c…

MALICIOUS

PDF

69.3 KB Created: 2021-05-27 22:38:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 99203c157b00cab7fd615e0b17c36072 SHA-1: d09c71bde4eee24ee08f2377e5bc6a7984b210f0 SHA-256: d1983d9bd6bf8e5cedfbeaafeaf0e4638deff59864b38e6377a4acb274f761b2
156 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised WordPress sites, suggesting it is part of a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a malicious document designed to exploit user curiosity about salary information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://wastran.ru/uplcv?utm_term=how+much+do+biomedical+scientists+earn+in+south+africa+per+month PDF link annotation
    • https://noble-worldwide.com/wp-content/plugins/super-forms/uploads/php/files/f01d4eeb87eab732f1a3de97e844d987/40549502962.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb1666f0ab---palasedati.pdfIn PDF document text
    • https://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/80d84f664680bd348a71eaf0901ed7b4/437860696.pdfIn PDF document text
    • http://beytarimcilik.com/admin/editor_resim/file/71449366418.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160888e0c4b4f3---23408702934.pdfIn PDF document text
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/08910189a5732a828f00c7a1c6074dfe/93549779089.pdfIn PDF document text
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/bc1bd4b642abe37e411e88eee64f702e/52847705309.pdfIn PDF document text
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/e35d2b5537c452da996c792fb237ce62/solid.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16080c8e9ab21f---zezefobejunevobamuniselux.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d391b3a2ce---40872841114.pdfIn PDF document text
    • https://www.electriclighting.com/wp-content/plugins/super-forms/uploads/php/files/86acc9cb4d4d902d2208a34c4a2b1f2c/68438973517.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a9d315e51b3---18725152596.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/4666c7188a018e526cb6e9990ffa78bd/29694329104.pdfIn PDF document text
    • http://swaminarayangm.org/userfiles/file/33723088489.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_off0000ced8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCED8 5588 bytes
SHA-256: 9c6ea54be87582c9b922f3cbda47afc87c7f549730f522899a3d2048cc7c0884
font_01_sfnt_off0000e1b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1B4 10796 bytes
SHA-256: ef4636b6e3157b4cb264dd3b20e8c69ad5302edb0f3dbcc04df25ab6bcf48946