Malicious PDF — malware analysis report

Static analysis result for SHA-256 a12d3fe077784eb8…

MALICIOUS

PDF

74.5 KB Created: 2021-02-22 02:06:19 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-17
MD5: 8745fdf55d1b15590a551960e2a9dfe7 SHA-1: b126f2ea8fdbcee0def776634c50543be6888d59 SHA-256: a12d3fe077784eb8d83e7f0241247db6be2238c8334a8b0c03afecfbc7d2db84
184 Risk Score

Malware Insights

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

The PDF contains multiple embedded links that are flagged as malicious redirectors. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, a tool often used to create malicious PDFs that leverage external links for their payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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 links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/wix?keyword=living+solutions+10+cup+coffee+maker In PDF document text
    • https://cdn-cms.f-static.net/uploads/4383699/normal_602ad782974da.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4404103/normal_5fe7bbd7d1c76.pdfIn PDF document text
    • http://helpforteam.com/pojosiluvapijc5ecq.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4384160/normal_5fee82010d7f7.pdfIn PDF document text
    • http://tugofexofuwaza.22web.org/123_magic_parenting_course_uk.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452376/normal_5fd2837108c32.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4481068/normal_5fc74a6a76a71.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425009/normal_601df853441bc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407314/normal_5fd6ed9182373.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449987/normal_601bb2ad76fa1.pdfIn PDF document text
    • http://muruxilirafet.iblogger.org/australian_infrastructure_investment_report_2019.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://nezenomawaza.epizy.com/rheumatoid_arthritis_deformities_icd_10.pdfIn PDF document text
    • http://pipotaxi.rf.gd/8108570360.pdfIn PDF document text
    • http://kojomazudogog.epizy.com/high_thread_count_sheets_too_hot.pdfIn PDF document text
    • http://jafimogapevov.rf.gd/chrome_plugin_to_video_from_website.pdfIn 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_off0000e709.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE709 5592 bytes
SHA-256: fddb3387b7d3fe4b98b99cc94c3403f29e960d8c06e26b237cd1e03c831ceda1
font_01_sfnt_off0000fa1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA1A 10240 bytes
SHA-256: 6dbe752d2e65f826604f4fdf9f1ac247a3c4e1f40ee3845a4bc307b776773c49