Malicious PDF — malware analysis report

Static analysis result for SHA-256 f53dc942c7c43847…

MALICIOUS

PDF

70.1 KB Created: 2021-10-01 13:48:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 6eb98c4584f4872eb5172d8bf9efa124 SHA-1: 23dd8463d3e1778dc1b98973a89389904e769abd SHA-256: f53dc942c7c438473c09132cb990d9e0540352bf83c2514fa6f8616b41393523
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The PDF contains numerous embedded URLs, with one pointing to a disposable domain ('the-bom.kr'), suggesting a link farm or redirection to a malicious payload. The presence of external URIs and the link farm heuristic strongly suggest this PDF is part of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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://the-bom.kr/upfile/files/kopawikijawusuvifumi.pdf In PDF document text
    • https://kipass.fr/userfiles/file/42951844025.pdfIn PDF document text
    • http://pusancard.com/userData/board/file/roworafe.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/ertp27e275730kmo0lebsb8qeb/9843220303.pdfIn PDF document text
    • https://bvphcn.bdata.vn/upload/files/31775659923.pdfIn PDF document text
    • http://nfraccon.org/userfiles/file/mupexol.pdfIn PDF document text
    • https://alrashed-alsaleh.com/userfiles/files/daxefuzotowojizulovizop.pdfIn PDF document text
    • http://ke-sen.com/userfiles/file/1630737818.pdfIn PDF document text
    • http://www.dilipprabhavalkar.com/images/file/tanofagudogubezanaw.pdfIn PDF document text
    • http://stl-hk.net/userfiles/37158897314.pdfIn PDF document text
    • http://technoprofile.ru/userfiles/file/gaxifodoxasapivezaxu.pdfIn PDF document text
    • http://protectakoteasia.com/ckfinder/userfiles/files/93977294665.pdfIn PDF document text
    • http://toyotaquangninh.org/data/dulieu/files/virerag.pdfIn PDF document text
    • http://manvilastrust-org.bvirani.com/ckfinder/userfiles/files/9400965928.pdfIn PDF document text
    • http://hunicorn.hu/userfiles/file/44374258035.pdfIn PDF document text
    • http://rtm-plus.ru/ckfinder/userfiles/files/86709887167.pdfIn PDF document text
    • https://ezsprinting.com/userfiles/file/rozawuvusuxome.pdfIn PDF document text
    • http://sushinamu.com/uploads/files/90159150338.pdfIn PDF document text
    • http://clear-es.net/yamituki-n/uploads/files/fozifizexi.pdfIn PDF document text
    • https://sportsslife.net/upload/ckfinder/files/nawemurire.pdfIn PDF document text
    • http://zlhk.ru/upload_picture/file/84036473264.pdfIn PDF document text
    • http://harposwebdesign.nl/app/webroot/files/userfiles/files/zupemukedejemasowusuwi.pdfIn PDF document text
    • http://cappellastudio.it/userfiles/files/8851477429.pdfIn PDF document text
    • http://yhbinternational.com/userfiles/file/78938548794.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=god+of+war+chains+olympus+psp+isoPDF 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_off0000b1da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1DA 10992 bytes
SHA-256: 3d6794b9356af5ef21afaf84708080f6ef888990f79e167b8bb63752ea82e0ab
font_01_sfnt_off0000cb41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB41 15344 bytes
SHA-256: ae78fedcd44cca844d1b4d5e5f92e60dbc9b613ba815db17a0ab89129c8d7b91
font_02_sfnt_off0000f261.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF261 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1