Malicious PDF — malware analysis report

Static analysis result for SHA-256 2f9cbea43f166feb…

MALICIOUS

PDF

87.8 KB Created: 2021-07-14 10:10:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 4af7a5bf7d0a966c72a87abe6459984a SHA-1: 687a3c5115b2fd6723aa55f0cad39f7d9ff02a22 SHA-256: 2f9cbea43f166febc1652f0d1f06ce92714875bdb387d92d076094bbe1e3e634
156 Risk Score

Malware Insights

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

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to potentially compromised WordPress sites or disposable hosting, likely to lure users into downloading further malware or engaging in phishing. The presence of external URIs and link farm heuristics strongly suggests a distribution or redirection mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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 https://smidgel.ru/uplcv?utm_term=applied+numerical+analysis+pdf+download PDF link annotation
    • http://namjapizza.com/app/webroot/files/10562141687.pdfIn PDF document text
    • http://businesslegalgroup.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/sunufeteje.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160714caf655b5---39518074490.pdfIn PDF document text
    • https://mosconi.net/userfiles/file/vodajela.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1609e4f81d7072---nawebemowo.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609845a5858ff---besepafapolemijixeduj.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/160ec459223532---tesabaluruvewebuzafevuvil.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16098ea900af36---25496428389.pdfIn PDF document text
    • http://dental-forum.ru/userfiles/file/12167246189.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ddfc01f85d---buvagexadakerereze.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/vn9113sg410t1qjrtm5v3so0k3/tipudobofu.pdfIn PDF document text
    • http://moscowprice.com/content/xuploadimages/file/popogojimulovudul.pdfIn PDF document text
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/63c9c6974e263dedbf1ea9468fa84bb2/misupaxokewawasojudug.pdfIn PDF document text
    • https://bbpartner.cz/userfiles/file/63732029020.pdfIn PDF document text
    • http://akinmedikal.com/uploads/file/11287814017.pdfIn PDF document text
    • http://beastyenergy.com/userfiles/file/30467208317.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16088ade8f1b27---vajekemenadanifabopuragad.pdfIn PDF document text
    • https://assurancemauricie.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0fed74bacf---kokufulanizaxejipurigit.pdfIn PDF document text
    • http://bm-shower.com/userfiles/files/gunujenet.pdfIn PDF document text
    • http://shinserviceodi.ru/wp-content/plugins/super-forms/uploads/php/files/e5157a9aa1a640e834b2e7dfe8394073/47293600823.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/b5eba688051e012cf24f925fcf008901/lilusijekomewad.pdfIn PDF document text
    • http://biomassasia.net/data_ed/userfiles/file/6441126506.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/gvo3jf2ehn2nktn93nreeeli00/19309117923.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608eea27c032f---11751801448.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/0e104bcf1fe86cb3b11dbc55bb8a5261/14914396679.pdfIn PDF document text
    • https://bloomeng.com/uploads/20797945959.pdfIn PDF document text
    • http://lineshare.net/upload/files/20210625081435.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_off0000f0f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010908.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10908 10964 bytes
SHA-256: 46077e9db08d3a7eec89f6a4f33280414054622c4123304e400ed74295ac1b41
font_02_sfnt_off00012286.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12286 18124 bytes
SHA-256: bea8cd290eeb95d801c41ceb5189cd73409bfc1a032d577a8e03f668cbf9fb51