Malicious PDF — malware analysis report

Static analysis result for SHA-256 d3adc6ad4c195ffa…

MALICIOUS

PDF

88.1 KB Created: 2021-07-18 17:41:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 4d53ebd23f8f267b487d54ea020a2468 SHA-1: fe654dd25f2620f22a9116ef87a07f668990fafd SHA-256: d3adc6ad4c195ffa3f8b2418138e2ad37bddce587a066f06a7b5d584893df3eb
96 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to compromised WordPress sites, indicating an attempt to redirect users to malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious link farm. No scripts were extracted, and the document body was unreadable, so the primary attack vector appears to be the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/c14ffc3de2d6801ce371907e9c0e1ed5/72984085889.pdf In PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607cc44878b00---63283228966.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160897d508af57---welanazefugesu.pdfIn PDF document text
    • https://pt2-turbo-j3t.com/contents//files/38378544324.pdfIn PDF document text
    • http://nhatminhtrading.vn/app/webroot/uploads/files/xiluxusutat.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/49056491501.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/pdmfb6s6m8r9gk44av1k7p2h85/golumekavugusizus.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a141e14d04c---xogeperamejebujukenebat.pdfIn PDF document text
    • http://steelbo.com/uploads/admins/u0/files/20210608030922.pdfIn PDF document text
    • http://woori-tour.kr/FileData/ckfinder/files/20210716_7C7BCF9EBE696AA6.pdfIn PDF document text
    • http://twfbs.com/ckfinder/userfiles/files/89746424739.pdfIn PDF document text
    • https://ibeguiristain.com/userfiles/files/6809994452.pdfIn PDF document text
    • https://www.jscorporation.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/16096fe27e3dc0---25285837322.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c8b8dedcdcd---1832807641.pdfIn PDF document text
    • http://sarljarry.fr/userfiles/file/sulit.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160909cc634ef4---vigobobitifewin.pdfIn PDF document text
    • http://beijingbeat.com/contents//files/13441237077.pdfIn PDF document text
    • https://www.scilights.com/wp-content/plugins/super-forms/uploads/php/files/a70d518205a5940aedba7795e10931f9/86197494176.pdfIn PDF document text
    • http://xn--clinicaquirogavilario-vbc.com/wp-content/plugins/super-forms/uploads/php/files/u00ev6vaeajf04jcq7a0fhmtf5/nenof.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/782bb6a452757b12ef12d0114f54a356/46201639675.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a3124d411f0---muvodake.pdfIn PDF document text
    • https://adepotcustom.com/UploadFiles/file/20210623031922198.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a52164162e0---13042245138.pdfIn PDF document text
    • https://spectrumohio.com/wp-content/plugins/super-forms/uploads/php/files/00f8d42aab71ccc35ad4a641d96fa71e/31195724438.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/lt8pqrc4i42h4nn1r2b1lau0un/mubusepepifisoru.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=agricultural+crisis+in+india+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_off0000f338.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF338 17476 bytes
SHA-256: cb3263b0a545dc3e889894692f6bafa516d2b75ab096c646f0017de763b0dce6
font_01_sfnt_off00012117.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12117 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001392e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1392E 10624 bytes
SHA-256: db15285def29f7579545539f6a0e16974b3d7eae276735b255bd781700c14288