Malicious PDF — malware analysis report

Static analysis result for SHA-256 188717dcd27c1c12…

MALICIOUS

PDF

68.8 KB Created: 2021-09-13 16:04:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 71b642bf4cc75b3dc987b38ecd2bafbb SHA-1: a0446e1b0b2f12603c721c5a969af194e7244db1 SHA-256: 188717dcd27c1c12be2eea526c9e836fbf2f04f832fb6a2f2c222c88041a6c30
134 Risk Score

Malware Insights

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

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript. This JavaScript is likely responsible for downloading and executing a secondary payload, as suggested by the PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics pointing to a link farm on disposable hosting. The presence of embedded JavaScript and the nature of the URLs strongly suggest an attempt to exploit the user, likely via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9849

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://locnuocvietmy.com/Images_upload/files/vutiwefevebub.pdf In PDF document text
    • http://deaprogettazioni.it/userfiles/files/5454664155.pdfIn PDF document text
    • http://aftp.bg/userfiles/file/dipazodeluraxozefefiwosug.pdfIn PDF document text
    • http://businessnavigator.in/ckeditor/uploads/files/vataloriwufedilubataw.pdfIn PDF document text
    • http://ave-france.com/pics/files/bagikubodadexa.pdfIn PDF document text
    • http://interfacetravels.com/app/webroot/js/ckfinder/userfiles/files/64979693159.pdfIn PDF document text
    • https://baobiachau.com/luutru/files/wulum.pdfIn PDF document text
    • http://stadtbild-intervention.de/Quansis/ckfinder/userfiles/files/97815525390.pdfIn PDF document text
    • http://adirondackseafood.com/ckfinder/userfiles/files/37551181390.pdfIn PDF document text
    • https://wsbtitan.com/images/file/36523562906.pdfIn PDF document text
    • http://boldogelet.hu/media/38941596616.pdfIn PDF document text
    • http://cokhihoaiduc.com/uploads/files/60226365352.pdfIn PDF document text
    • http://www.ciesol.com/ckfinder/userfiles/files/ririlugebit.pdfIn PDF document text
    • http://matras-devison.ru/upload/file/fubozozub.pdfIn PDF document text
    • https://ribaczpeter.hu/files/file/viberetazulal.pdfIn PDF document text
    • http://johnlillylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/94103880676.pdfIn PDF document text
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/16131af26678b6---toxigotuz.pdfIn PDF document text
    • https://ww150001.linebot.net/upfile/files/20210909093308.pdfIn PDF document text
    • https://secolink.sk/userfiles/file/rafiroxemawatug.pdfIn PDF document text
    • https://cuisinescartier.ca/upload/editor/file/84220645451.pdfIn PDF document text
    • http://jullien38.com/ressource/site-image/files/15773476590.pdfIn PDF document text
    • https://speak82.com/_UploadFile/Images/file/68282894270.pdfIn PDF document text
    • http://a2hgghk.handylover.com/upload/files/34033775686.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613729b47a728---50022026913.pdfIn PDF document text
    • https://toyotaautobody.com/ckfinder/userfiles/files/48553076102.pdfIn PDF document text
    • http://yushendesign.com/images_fck/file/1630894570.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=textview+animation+androidPDF 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_off0000b138.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB138 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c94a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC94A 14772 bytes
SHA-256: 9dabaf18c9515a75b7f82468ce3b94769371f9b95c3d4293d29d964c727a441b
font_02_sfnt_off0000ee35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE35 10412 bytes
SHA-256: 4c68e42ba308c6f711bd0509d8130a6795ab911f7b5f76a0e5cb1900e518d8bb