Malicious PDF — malware analysis report

Static analysis result for SHA-256 9febef8d6da03b98…

MALICIOUS

PDF

84.6 KB Created: 2021-09-16 20:18:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 21a4bc31fa236cf96c092a16c3d7e104 SHA-1: 460a0bc03101dc760eea5587e2c3293e79f8438b SHA-256: 9febef8d6da03b9849edd2f7867c8e0ab725c9c6b7ce8a364f841e2322bd64bf
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and numerous external links point towards an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://infrive.ru/uplcv?utm_term=file+sharing+app+between+pc+and+android PDF link annotation
    • https://univerosg.com/ckfinder/userfiles/files/wobatujajowutibemepuz.pdfIn PDF document text
    • https://kabelkyaobuv.sk/editor_uploads/files/vopetujezabosawipemip.pdfIn PDF document text
    • http://velapower.com/glwh/UploadFile/file/2021090716023373499.pdfIn PDF document text
    • http://ampletrekking.com/userfiles/file/22240407862.pdfIn PDF document text
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/90368618408.pdfIn PDF document text
    • http://longtra.vn/userfiles/file/korevezanegi.pdfIn PDF document text
    • http://secretinvitation.net/images/files/jerafameferituramomaka.pdfIn PDF document text
    • https://tonymusic.se/UserFiles/files/64854054856.pdfIn PDF document text
    • https://cafemocion.com/userfiles/file/tufalupekezumelawunaz.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139efdf0c621---malesiboxavo.pdfIn PDF document text
    • https://serrechevalier-skifun.com/imagesfile/mepewoxemubarewumev.pdfIn PDF document text
    • http://ivankrivanek.com/userfiles/file/jifopazanexomidedawora.pdfIn PDF document text
    • http://petukmahaaaraj.com/userfiles/file/55486486022.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/sidetenejirufageverebitox.pdfIn PDF document text
    • http://sushikyototogo.com/uploads/files/41852706317.pdfIn PDF document text
    • http://anneadamslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/57907901429.pdfIn PDF document text
    • https://bodegoncriollo.com/userfiles/file/21898625471.pdfIn PDF document text
    • https://cfaegaianascente.pt/portal/userfiles/files/xisibosijebokeko.pdfIn PDF document text
    • http://fc-junajted.com/upload/datoteke/gifejuzepenekumizul.pdfIn PDF document text
    • https://shen-su.eu/gfx/userfiles/files/67738539969.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/021058387569.pdfIn PDF document text
    • http://petukmahaaaraj.com/userfiles/file/63162374278.pdfIn PDF document text
    • https://mimpishio1bet.com/contents/files/1731956909.pdfIn PDF document text
    • http://phupmirpol.pl/userfiles/file/sanuk.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_off0000e6f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6F8 10996 bytes
SHA-256: 696d49f6edb756a0eaec7ac91e588e08d6c6e1885f9970c774dea88093ea87fc
font_01_sfnt_off00010011.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10011 17276 bytes
SHA-256: c741e607601f033e8c776066edef3a21522d4cdf0e787cdc9a6f075003cb883c
font_02_sfnt_off00012ce8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12CE8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1