Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3fed37949021a62…

MALICIOUS

PDF

83.0 KB Created: 2021-09-19 03:18:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: d4b5fadf4e0400db6d8d8fb8c510afea SHA-1: ea8049d7d140c611167cd92ee74947fe35c5138a SHA-256: c3fed37949021a6216b9c468a404db7948ad835d9fa2da46bc59bae078c2da25
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to a link farm, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent. The primary attack pattern involves directing users to these external links, which likely serve as a gateway for further malicious activity such as phishing or malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://topmebli.com/content/xuploadimages/file/59793037733.pdf In PDF document text
    • http://mibenjamin.com/userfiles/file/68491638213.pdfIn PDF document text
    • https://hobbes-group.com/upload/files/zudedijakuzekigifegat.pdfIn PDF document text
    • http://incomsistema.ru/ckfinder/userfiles/files/81050661266.pdfIn PDF document text
    • https://classykitchen.pl/web/uploads/files/dapova.pdfIn PDF document text
    • http://www.heksan.com.pl/file/7170503019.pdfIn PDF document text
    • http://rowadhr.com/app/webroot/upload/files/40733622866.pdfIn PDF document text
    • http://qiuyutv.com/userfiles/files/20210919081541.pdfIn PDF document text
    • http://detaycopymatbaa.com/userfiles/file/42947559635.pdfIn PDF document text
    • http://exhibitionchannel.com/upload/22178333770.pdfIn PDF document text
    • https://globalybm.com/ckfinder/userfiles/files/1631508589.pdfIn PDF document text
    • http://montpellier-businessplan.eu/mbp/upload/images/images/upload/ckfinder/65088130745.pdfIn PDF document text
    • https://firstview.christoff-design.com/files/74623630857.pdfIn PDF document text
    • https://sanaspinler.com/calisma2/files/uploads/betikanujalusekinitoxe.pdfIn PDF document text
    • http://matras-devison.com/upload/file/ponovozazijukokobujupinom.pdfIn PDF document text
    • http://scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/nipolovujepofajevo.pdfIn PDF document text
    • http://cobe-ing.it/userfiles/files/38742996187.pdfIn PDF document text
    • https://www.icicle-mountaineering.ltd.uk/ckfinder/userfiles/files/romefujawajimepuperabit.pdfIn PDF document text
    • http://studioindelicato.com/userfiles/files/jivuvuwozosumarasurunu.pdfIn PDF document text
    • http://acupunctuuryao.nl/ckfinder/userfiles/files/tilurixaposakudarulaxipi.pdfIn PDF document text
    • http://pfmconsulting.org/survey/userfiles/files/kelekolatudosamodir.pdfIn PDF document text
    • https://luatkhangthai.vn/upload/fck/file/ponorubadoj.pdfIn PDF document text
    • https://russiancosta.ru/ckfinder/userfiles/files/4335027771.pdfIn PDF document text
    • http://sakesushilakehavasu.com/uploads/files/wimivafaxavif.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=buy+chal+mera+putt+2PDF 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dfdc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFDC 10540 bytes
SHA-256: b4f61ae19c4413bbff93ce48c24b2bc2b437020a90c074fb4a87e4580ac07011
font_01_sfnt_off0000f807.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF807 17712 bytes
SHA-256: 492eeb0f3c0f9c8e4ab1b07e50adb0dfe6953825d599768681ccddc7fca146fa
font_02_sfnt_off0001269c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1269C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1