Malicious PDF — malware analysis report

Static analysis result for SHA-256 10baa6b79e19fab3…

MALICIOUS

PDF

69.6 KB Created: 2021-09-27 17:51:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: d6785bcde917fb2a9a25bac0b6e2f0e0 SHA-1: e1f49b20f7338ec9d4ad0ac99a814cb9e8d97a94 SHA-256: 10baa6b79e19fab3cec77c070463c69113d69a44b3ec25b5d2e754ea830aa24f
66 Risk Score

Malware Insights

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

The PDF document was flagged by an ML classifier as malicious with high confidence. It contains numerous embedded URLs pointing to a link farm hosted on various domains, many of which appear to be disposable. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using a large number of distinct hosts with few links per host, suggesting an attempt to manipulate search engine results or distribute malicious content. No scripts were extracted, and the document body was unreadable, but the URL structure strongly suggests a malicious intent to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 4

  • 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://willmarareachamber.com/ckfinder/userfiles/files/72377454312.pdf In PDF document text
    • http://pokewaveanaheim.com/uploads/files/64693109153.pdfIn PDF document text
    • https://www.nickelmarket.co.za/includes/ckfinder/userfiles/files/lepewiletexagew.pdfIn PDF document text
    • http://ckattorneys.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zowafi.pdfIn PDF document text
    • https://net-mex.hu/ckfinder/userfiles/files/58945512875.pdfIn PDF document text
    • http://bjerkelunden.org/content/files/userfiles/file///xaron.pdfIn PDF document text
    • http://kingalbertltd.com/uploadedfiles/file/togadole.pdfIn PDF document text
    • http://coutleelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/falasidanibusomapefazuk.pdfIn PDF document text
    • https://groupunsur4.com/contents/files/98937753247.pdfIn PDF document text
    • http://szolnokepul.hu/userfiles/file/61379624867.pdfIn PDF document text
    • http://karcannakliyat.com/userfiles/file/latedomigagadolelopefej.pdfIn PDF document text
    • http://achilleferolla.it/userfiles/files/87182669346.pdfIn PDF document text
    • http://euro-ex.com/images/blog/file/17056833572.pdfIn PDF document text
    • https://niboparis.com/upload/fckeditor/file/1632005432_1.pdfIn PDF document text
    • http://ebiocell.com/uploadfile/file///2021092715022972.pdfIn PDF document text
    • http://eltdb.com/UserFiles/files/ribazurizuwiselotigod.pdfIn PDF document text
    • http://shopcloud.cloud/ckfinder/userfiles/files/gowuboxubirodupelinoto.pdfIn PDF document text
    • http://ore-processing.ru/d/files/1096182814.pdfIn PDF document text
    • https://araprinter.com/ckfinder/userfiles/files/97943807761.pdfIn PDF document text
    • https://berbagiangka.com/contents/files/vigiz.pdfIn PDF document text
    • http://zekejozsef.eu/FCKfeltoltott/file/86286283788.pdfIn PDF document text
    • http://ccforum.kr/uploads/file/1632329961.pdfIn PDF document text
    • http://tupnate.com/ckfinder/userfiles/files/jusuzakurogedidimidaran.pdfIn PDF document text
    • http://aromata.ru/upload/files/wivatibekitalakurefalodak.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=is+eating+spinach+good+for+youPDF 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_off0000b262.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB262 14744 bytes
SHA-256: d767a2bb793a7de2d7e0bad28cdd0bb1f134c1b6bce2c54f1f0b06c20e14f8f9
font_01_sfnt_off0000d74a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD74A 11016 bytes
SHA-256: 691743a6bb585a900c9455f9e62fa727d45e5f6cd1c98fd8f8a553160dfe35c5
font_02_sfnt_off0000f0b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0B2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1