Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab8a25a6344f5535…

MALICIOUS

PDF

76.5 KB Created: 2021-09-16 22:52:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: ff03cd923447c66d0c33d348ed2500a7 SHA-1: 4f5c60e135fbf5ce6d7a1fa64092a60dd54d61e7 SHA-256: ab8a25a6344f5535aee1bbefacef3a0e3eb67bf8554339f8d78b6c197a444459
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that form a link farm, many of which point to potentially compromised websites or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the ML classifier 'ML_NYX_PDF_MALICIOUS' strongly indicate malicious intent, likely to trick users into downloading further malware by posing as a useful tool. ClamAV also detected this as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 6

  • 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.
  • 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://huntic.ru/uplcv?utm_term=pdf+to+excel+free+online+converter+free PDF link annotation
    • http://cityfate.com/files/files/lakevomolufitixa.pdfIn PDF document text
    • http://lifeline-sports.com/files/file/zakebigojajimir.pdfIn PDF document text
    • http://smarttechsolutionukltd.com/uploaded_files/userfiles/files/nezazonatelovewoji.pdfIn PDF document text
    • http://sobinco.cz/ckfinder/userfiles/files/12256224145.pdfIn PDF document text
    • https://bccphil.paramedix.biz/uploadfiles/file/sapifipiwiditoja.pdfIn PDF document text
    • http://josepholszowka.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sowula.pdfIn PDF document text
    • https://asiahealth.standrewsdentalsurgeons.com/ckfinder/userfiles/files/luvufitavikemifesolepomo.pdfIn PDF document text
    • http://wintec-samu.hu/uploads/files/jeraxe.pdfIn PDF document text
    • https://dortmundpools.com/contents/files/7435122204.pdfIn PDF document text
    • https://madhubanindiancuisine.com/nbloom/fckuploads/file/sokoki.pdfIn PDF document text
    • http://visusmarble.com/images_upload/files/97118245044.pdfIn PDF document text
    • http://kangmeideyiliao.com/uploadfile/file///2021090609035783.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16140629c0d994---79691585360.pdfIn PDF document text
    • http://tulga.ru/editor/files/xaxubirizunuwejulaxunok.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/db4f22402ffc2ede4dd749ecf2d733b6/dujoxi.pdfIn PDF document text
    • http://1carl.com/userfiles/file/wowonagofi.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161319b8a5e2d5---tuvirarusafijulonak.pdfIn PDF document text
    • http://pinxedien.net/upload/files/18086930438.pdfIn PDF document text
    • http://snft.ro/media/file/66111030927.pdfIn PDF document text
    • http://neoneofitou.com/ckfinder/userfiles/files/10334552979.pdfIn PDF document text
    • http://vallovin.it/userfiles/files/61650546953.pdfIn PDF document text
    • http://soundspace.eu/Upload/file/2771156728.pdfIn PDF document text
    • http://altronic.pl/!mag2011/userfiles/file/28020734611.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/85b760e07797cd261fe0ad41d834d746/sejatafebakevu.pdfIn PDF document text
    • https://netlandschool.cl/files/buroziruvesevasezaxorup.pdfIn PDF document text
    • https://nilsahost.com/calisma2/files/uploads/4443848793.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://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_off0000c0f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC0F2 19820 bytes
SHA-256: b7de2dd3dbc12d3bfb0b7798ac0a0fc15b397a87ea082356c60c9a272385d587
font_01_sfnt_off0000f416.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF416 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010c2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C2D 10308 bytes
SHA-256: a0e65829d57fb536a55e90243d8fce6ccfa6fa28658e52a2dcd8a83cc44da58f