Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a31fd86eb394a18…

MALICIOUS

PDF

86.5 KB Created: 2021-09-20 07:54:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: a15eeae41b14a676027d3033e64e93e4 SHA-1: 477f762d069bfdce0c6af0bf420417e036879267 SHA-256: 9a31fd86eb394a1894c2ab84f7fcd3754c4b86a110f2439c21de6dd8385a3b61
134 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external URIs, indicating it is designed to redirect users to malicious websites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports the attack pattern of using numerous links on disposable hosting to obscure the true malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://crysiq.ru/uplcv?utm_term=ultra+street+fighter+apk PDF link annotation
    • http://tdvvietnam.vn/webroot/img/files/74232592200.pdfIn PDF document text
    • http://supermarketdv.ru/files/file/judavur.pdfIn PDF document text
    • https://traveletrust.com/basefile/traveletrustcom/files/35112494686.pdfIn PDF document text
    • http://veterinariomauracotti.it/userfiles/files/paxunofuvetokimoketamawon.pdfIn PDF document text
    • http://modernplating.com/userfiles/file/30093628895.pdfIn PDF document text
    • https://weddingitaly.jp/images/file/sumisafopet.pdfIn PDF document text
    • http://ultraljud.nu/bild/files/22847756354.pdfIn PDF document text
    • https://guadix.co/ckfinder/userfiles/files/kalomezinazupuxe.pdfIn PDF document text
    • http://www.de.ruben.pl/ckfinder/userfiles/files/fenalijobak.pdfIn PDF document text
    • http://sluchatka-shop.cz/files/upload/files/pazoruzoregowisik.pdfIn PDF document text
    • https://semagro-msw.ru/pics/images/file/46992174312.pdfIn PDF document text
    • http://sushi-belovo.ru/files/57937106251.pdfIn PDF document text
    • http://ekbdrive.ru/ckfinder/userfiles/files/dexixudir.pdfIn PDF document text
    • http://wojno-stal.pl/pliki/file/rafasega.pdfIn PDF document text
    • https://juniorclublivorno.com/sitonews/images_upload/files/misorajo.pdfIn PDF document text
    • http://italy-ex.com/images/blog/file/9669866783.pdfIn PDF document text
    • http://glamour-nsk.ru/ckfinder/userfiles/files/fasalurafamedadudi.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/16132a0ecd05ad---59847174458.pdfIn PDF document text
    • http://arenda-v-novosibirske.ru/ckfinder/userfiles/files/93136308308.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/ejhljickgm18labkcs1mslasgf/23578239480.pdfIn PDF document text
    • http://akcihlar.cz/userfiles/file/sumatu.pdfIn PDF document text
    • http://portofmiamitunnel.com/system/js/back/ckfinder/userfiles/files/58129761735.pdfIn PDF document text
    • http://daiduongmetal.com/uploads/ckfinder/files/57349396245.pdfIn PDF document text
    • http://drsrkbedcollege.com/ckeditor/ckfinder/userfiles/files/38025442436.pdfIn PDF document text
    • http://circuitvietnamcambodge.com/hinhanh/file/romumebovegofin.pdfIn PDF document text
    • https://sunridgecorp.com/uploads/files/202109121412411218.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_off0000e295.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE295 10512 bytes
SHA-256: 3df92b9427f3d823d04335b075b95a00349ab8c10e4dbc6efcbad8e41ccac3d4
font_01_sfnt_off0000faa9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAA9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000112bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112BB 22020 bytes
SHA-256: acec7c0fb7638c771c07f341d29c74c67ae2e012a74836b87c12a07bb2628606