Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b3a9ca504a6d0e1…

MALICIOUS

PDF

68.2 KB Created: 2021-09-15 18:10:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 3ba8b0005c39f4d3c53baf2450f56793 SHA-1: fa7703736e3a11bdc46f0a525a19159520f866c2 SHA-256: 9b3a9ca504a6d0e1a3e46692cb33b1fcacb6e06ffed8ca29f7a893d3622cbc08
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a malicious document, potentially leveraging embedded JavaScript for exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://wastran.ru/uplcv?utm_term=android+kitkat+emoji PDF link annotation
    • https://ebal.ro/app/webroot/files/userfiles/files/pasuvawaxilupetafunape.pdfIn PDF document text
    • https://dailyhondaotomientay.com/upload/files/zowukuteloginapisuvux.pdfIn PDF document text
    • http://squash-fitness.cz/userfiles/file/finokopabinerikonepoliba.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/agk8kdigi6t4vg6m78fnd32slj/midabifazefilofasevipak.pdfIn PDF document text
    • http://assytekservizi.com/userfiles/files/nejejiz.pdfIn PDF document text
    • https://salwangurugram.com/files/20594800385.pdfIn PDF document text
    • http://biswasi.com/userfiles/files/65446389576.pdfIn PDF document text
    • http://joeun-it.com/userData/board/file/sidevepufikizud.pdfIn PDF document text
    • http://gnatowski.pl/attachments/file/tisufixaloxemiwaxoguri.pdfIn PDF document text
    • http://hoya889.com/upfile/files/20210915213013.pdfIn PDF document text
    • https://duvanco.be/docs/files/naberatajetir.pdfIn PDF document text
    • https://www.scmsgroup.org/ckfinder/userfiles/files/77809499282.pdfIn PDF document text
    • http://mdfgiare.com/upload/files/kojunuziduwokunuwejasife.pdfIn PDF document text
    • http://dopuskvsro.ru/UserFiles/wixot.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f3e22f187e---jigunafarafozirukaf.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161415bf3cad59---kenizurotorepase.pdfIn PDF document text
    • http://sanmorales.es/userfiles/files/wawidolinaworemasaxepetel.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613099b965fc2---lavewabixagekapewuvuwomi.pdfIn PDF document text
    • https://naves.cz/res/file/pozosonofarus.pdfIn PDF document text
    • http://ellissi.org/userfiles/files/67640065841.pdfIn PDF document text
    • http://195exim.com/datas/files/puvopa.pdfIn PDF document text
    • http://weifong.tw/fckimages/file/purenemezikoladifo.pdfIn PDF document text
    • http://royalwedding.jp/images/blog/file/28178396378.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_off0000af5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF5D 14684 bytes
SHA-256: 050d19a7aed5017f7ec3e34eecf6aa14f904f2e30d983ed405581a017880ffc5
font_01_sfnt_off0000d3f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3F2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ec09.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC09 10400 bytes
SHA-256: e83108277eeac8fed75ebe14e3a7ef793a0f2d79a8cf0b913720ada268063ddd