Malicious PDF — malware analysis report

Static analysis result for SHA-256 b529097e18d301f5…

MALICIOUS

PDF

87.2 KB Created: 2021-09-12 06:04:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e32cbff34275659e77df238e1e1e8d31 SHA-1: 798b5131b26306f6e063fa93281554d7e2ed4826 SHA-256: b529097e18d301f5d63fa5478b42ca3f7e2cb89882b44a930fd993712b6eef06
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, containing numerous external URIs pointing to various domains, likely to obscure the true malicious destination. The presence of embedded URLs and the link farm structure strongly suggest an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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 http://cauthangdep24h.com/upload/files/80557870018.pdf In PDF document text
    • http://giteduguedesboires.com/userfiles/file/17037782405.pdfIn PDF document text
    • https://elemental-ia.com/userfiles/file/zuwefijoxubupi.pdfIn PDF document text
    • http://cathugo-yachts.de/res/wysiwyg/file/11297187402.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/161371cb7d222c---3923814226.pdfIn PDF document text
    • http://thementalhealthadvocates.org/files/userfiles/file/30148797195.pdfIn PDF document text
    • http://quantri.thaisonpalacehotel.com/upload/files/gipusenidiluriv.pdfIn PDF document text
    • http://ccswcd.com/userfiles/file/36897657041.pdfIn PDF document text
    • http://ducnhua.com/upload/files/latufor.pdfIn PDF document text
    • http://ciaomamma.hu/editor_up/bedut.pdfIn PDF document text
    • https://odlingfamily.com/userfiles/file/57211351363.pdfIn PDF document text
    • http://exosushi.com/uploads/files/9703061381.pdfIn PDF document text
    • https://nenmongdangquang.com/upload/files/konowonolopefesex.pdfIn PDF document text
    • http://mybyblos.com/userfiles/file/garaminixikurififafep.pdfIn PDF document text
    • https://acrgruppe.de/userfiles/file/89059897587.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/161383a90c5b6c---7545819577.pdfIn PDF document text
    • http://parateam.cz/file/86609764853.pdfIn PDF document text
    • http://plaschke-partner.com/uploaded/file/22610836165.pdfIn PDF document text
    • https://mackbeks.com/files/file/63412249867.pdfIn PDF document text
    • http://rm-centr.ru/uploads/file/jowedanagufisiredatakozof.pdfIn PDF document text
    • https://omprintandpack.com/userfiles/file/67591204320.pdfIn PDF document text
    • https://korzayithalat.com/spot/admin/fckeditor/userfiles/file/wibofebusudugelelakab.pdfIn PDF document text
    • https://fuoriscena.eu/file/39256937842.pdfIn PDF document text
    • http://jjsgreatescape.com/uploaded_files/userfiles/files/gobosupuzaxexurekovu.pdfIn PDF document text
    • http://88cpap.com/userfiles/files/11456005763.pdfIn PDF document text
    • http://anhhieu.vn/hinhanh/file/makoxiwibanogesowovuk.pdfIn PDF document text
    • https://tucarrorentacar.co/ckfinder/userfiles/files/77630972582.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=sao+launcher+appPDF 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_off0000f03c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF03C 10288 bytes
SHA-256: 09d0f762e10c41cdf5b3d93f2ca3a2dcccd7f24ea6813949702c58fd7be2be4e
font_01_sfnt_off0001074f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1074F 17892 bytes
SHA-256: fca5e34a77a70968420c385c1dee8dbfd51df041b037fdd896d46a6f72f4b928
font_02_sfnt_off00013689.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13689 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1