Malicious PDF — malware analysis report

Static analysis result for SHA-256 91b5876401f62a09…

MALICIOUS

PDF

72.1 KB Created: 2021-09-09 19:16:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: ee6995b15b51ef4be575e420b5b46f7c SHA-1: b7b5df64db341586b2ff39bfb6dfe2d5a35c421d SHA-256: 91b5876401f62a094a57326fc35d3d4eaf6bb1c990a07f5faddb7748a9381b46
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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
  • 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://philabc.ru/uplcv?utm_term=tanki+online+free+crystals PDF link annotation
    • https://actor-conseil.com/files/file/43187604354.pdfIn PDF document text
    • http://rorolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/95183587135.pdfIn PDF document text
    • https://motoralbini.it/files/file/25995822276.pdfIn PDF document text
    • http://kenhuffbuilders.com/userfiles/file/86172738675.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/ae3c75cb086557d685db1e8e3fa8f17b/10532804244.pdfIn PDF document text
    • https://alpasol.e-giant.net/upload/files/65207694882.pdfIn PDF document text
    • https://shunnasato.com/lokanizebaresomulotata.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612fe320b9df9---7767125552.pdfIn PDF document text
    • https://vieclamlaocai.vn/webroot/img/files/nimosimevonu.pdfIn PDF document text
    • http://uniquecharacters.com/upload/files/vugimixow.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161369facbd0bb---nikigibidewezakodipedet.pdfIn PDF document text
    • http://thomasgearon.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/gijebe.pdfIn PDF document text
    • http://transbur.ru/admin/ckfinder/userfiles/files/43263359502.pdfIn PDF document text
    • http://kanchanaspa.com/ckfinder/userfiles/files/34916277074.pdfIn PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139d944c3f02---sowibedusudumepuwa.pdfIn PDF document text
    • https://optimuselearningschool.aels.edu/learning/site/images/uploadfiles/55755671962.pdfIn PDF document text
    • https://ecpa.fr/uploaded/file/56791348977.pdfIn PDF document text
    • http://entryexpress.online/chapter_images/files/42663174874.pdfIn PDF document text
    • http://sashtraayurveda.com/ckfinder/userfiles/files/waxosibibizarukezexelika.pdfIn PDF document text
    • http://chiari-web.com/ckfinder/optimist/files/21274284230.pdfIn PDF document text
    • http://hc6999.com/userfiles/files/7402524154.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_off0000b68b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB68B 17452 bytes
SHA-256: ba29cdc27d4fe6c62b8d3fea663e108e8fe39ac7ca458ff87a0e35308832dadd
font_01_sfnt_off0000e345.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE345 10500 bytes
SHA-256: 9d5aa0f5897a24db1861f92b39507795787e3eaaed7a854c4e9ad00ca9f5e33b
font_02_sfnt_off0000fb5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB5F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1