Malicious PDF — malware analysis report

Static analysis result for SHA-256 ffa6dc53acb49398…

MALICIOUS

PDF

79.0 KB Created: 2021-09-16 11:31:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 144b104c856c05a659da0dda7601bb38 SHA-1: e81b2fab0497a9c32750c3ec953e51a4f6f658f5 SHA-256: ffa6dc53acb49398d0e65a1f24822a17640d883bc1dbec31ac33ae2dbfd2437b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attack pattern involving directing users to potentially harmful external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://igigeothermal.jp/userfiles/file/visukazame.pdf In PDF document text
    • http://malagi.pl/user-files/fck/file/15349426638.pdfIn PDF document text
    • https://www.colegiodesafio.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1614063a860731---pemusitiredo.pdfIn PDF document text
    • http://thewhitmerlawfirm.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/69493289674.pdfIn PDF document text
    • http://acecaalcoy.com/userfiles/file/15852912108.pdfIn PDF document text
    • https://www.info-service.com.tw/plugin/ckeditor/ckfinder/userfiles/files/zubomefalevu.pdfIn PDF document text
    • http://veitali.com/upload/files/53003460036.pdfIn PDF document text
    • http://ryanoomen.nl/uploadimages/files/68091455502.pdfIn PDF document text
    • http://maksimetall.ru/files/90565920622.pdfIn PDF document text
    • https://clubkdo.fr/img/pics/files/32264514939.pdfIn PDF document text
    • http://bjhtdszdh.com/v15/Upload/file/20219121022391108.pdfIn PDF document text
    • https://fokusmedia.com/images/uploads/15130933221.pdfIn PDF document text
    • http://cocoal.com/uploads/file/73426246269.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613fc77c4686d---kubasogetekan.pdfIn PDF document text
    • https://hgindustrial.eu/userfiles/files/27977941940.pdfIn PDF document text
    • https://chingchia.com/uploads/files/202109021251076845.pdfIn PDF document text
    • http://narnivet.com/userfiles/files/77725320158.pdfIn PDF document text
    • https://chingchia.com/uploads/files/202109070857469518.pdfIn PDF document text
    • https://rarahil.org.np/ckfinder/userfiles/files/janevolalirilarilixekusar.pdfIn PDF document text
    • http://elosc.com/upFile/file///ITX202109100017204637.pdfIn PDF document text
    • http://touristclub.in/userfiles/file/kileriru.pdfIn PDF document text
    • http://trungtinjsc.vn/upload/FCK/file/90264551716.pdfIn PDF document text
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/1941be3c223fd1d9df61edee1f41319a/55602206152.pdfIn PDF document text
    • http://giaphatmed.com/upload/file/16632235990.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=asi+hablo+zaratustra+pdfPDF 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_off0000cacc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCACC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e2e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2E3 10640 bytes
SHA-256: 7a21a0c5bd1ebf6e0f9e5c4b8bb59e56dd4fdecba216bea0178a09266716a2c5
font_02_sfnt_off0000fb2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB2A 19940 bytes
SHA-256: c1e3b6d6e74eae2233d8c657427279ec86f25821223029c8300926abd5e7739a