Malicious PDF — malware analysis report

Static analysis result for SHA-256 b66d5f41ff493a7a…

MALICIOUS

PDF

81.7 KB Created: 2021-09-19 08:54:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 9185340d50a1f6e0e6ea5a16b0f1be49 SHA-1: fe2259f31082237b7af26f63d00cd68ea8d203e8 SHA-256: b66d5f41ff493a7aca541bdea9fcf47525b6210db9f377b71e9431f83933177d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to potentially compromised or disposable hosting. These links are likely intended to redirect users to malicious sites for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://permanentnimakeup-brno.cz/userfiles/files/wagudavet.pdf In PDF document text
    • http://greatnice.club/updatefiles/file/56582310524.pdfIn PDF document text
    • https://bimore.vn/webroot/img/files/fosirofiketonuk.pdfIn PDF document text
    • http://dishandspoonproductions.com/ckfinder/userfiles/files/pupekufidano.pdfIn PDF document text
    • http://saaretravel.ee/images/file/11899988717.pdfIn PDF document text
    • https://www.habitat-morvan.fr/ckfinder/userfiles/files/dakapekaberukutufefonoz.pdfIn PDF document text
    • https://vantainoidia.vn/ci/userfiles/files/11864612283.pdfIn PDF document text
    • https://indoshaolinkungfusociety.com/ckfinder/userfiles/files/mukebiforefototomuwanuroj.pdfIn PDF document text
    • https://sdhouse.info/ckfinder/userfiles/files/kururilobejaleverepulixun.pdfIn PDF document text
    • http://thanhnhomdinhhinh.net/uploads/files/doxililavasowa.pdfIn PDF document text
    • http://nhatnamvina.vn/rich_editor/file/2276867245.pdfIn PDF document text
    • https://cribpointonline.org/cribpointonline/userimages/file/56950364336.pdfIn PDF document text
    • https://colegiumaniucarei.ro/ckfinder/userfiles/files/vupigenobolexov.pdfIn PDF document text
    • http://chi-kara.net/Upload/files/fawabekiba.pdfIn PDF document text
    • http://autoset66.ru/admin/ckfinder/userfiles/files/mutojezabas.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/bd9f254s4iuhnaf7d6u31v5ako/pepuruwixe.pdfIn PDF document text
    • https://zenithoverseas.com/assets/userfiles/files/33364001668.pdfIn PDF document text
    • http://ty-universe.com/image/files/20210915_152446.pdfIn PDF document text
    • http://protetyka-lublin.com/images/wyswig_images/file/21779516113.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613f86e0882bd---52282645716.pdfIn PDF document text
    • http://besttailor.info/ckfinder/userfiles/files/45373542660.pdfIn PDF document text
    • http://shopcode.ru/uploads/file/16845497332.pdfIn PDF document text
    • https://ikitellirezistans.com/upload/files/51984800515.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140cf2301664---67498247672.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=2+0+1PDF 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_off0000ddba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDBA 18448 bytes
SHA-256: 224d267ed3d8d66d2ee80fc753c57996d2c1701621d0e956336b897111d6ead9
font_01_sfnt_off00010e59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E59 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001266f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1266F 9276 bytes
SHA-256: d5503d92b5c98793fc06c3d9693fae020fb8a3a71f1ccfd5f468136e1041e11c