Malicious PDF — malware analysis report

Static analysis result for SHA-256 12720eb4e3643fe7…

MALICIOUS

PDF

87.2 KB Created: 2021-09-15 16:35:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 490362b6e3de7b93af714e0033efd750 SHA-1: f2921afe2b845f52f93a346b5ac4bc8ef26310a4 SHA-256: 12720eb4e3643fe73d0a7b7eac827086224a2d068e355ca645b571b273027a66
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on various domains, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • 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.
  • 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://gintaras.cz/userfiles/file/dusilelatobadusipovuxeg.pdf In PDF document text
    • https://costarica4d.com/contents/files/91749484284.pdfIn PDF document text
    • http://sanarina-coaching.de/ckfinder/userfiles/files/sebumakidaji.pdfIn PDF document text
    • http://tfe-design.dk/userfiles/file/50407193148.pdfIn PDF document text
    • https://wietsevoermans.nl/ckfinder/userfiles/files/36433478664.pdfIn PDF document text
    • http://www.ecrivains-consult.fr/easyonline/ckfinder/userfiles/files/19412531950.pdfIn PDF document text
    • http://srcchaika.ru/files/uploads/files/93321522474.pdfIn PDF document text
    • https://dom4m.by/userfiles/files/fomufaje.pdfIn PDF document text
    • https://adsbudget.net/userfiles/file/nosowivizotikovi.pdfIn PDF document text
    • http://jungam21.com/upfiles/file/1631549101.pdfIn PDF document text
    • http://helenhotel.vn/upload/files/43874957992.pdfIn PDF document text
    • http://pc-driver.ru/userfiles/files/70475005614.pdfIn PDF document text
    • https://mercerapparelss.com/userfiles/files/65971467780.pdfIn PDF document text
    • http://flixgolf.com/ckeditor/ckfinder/userfiles/files/84103885133.pdfIn PDF document text
    • http://quartierdete.fr/uploads/fckeditor/file/gobozebutukebinabape.pdfIn PDF document text
    • http://meandnetworking.com/ckfinder/userfiles/files/32178342484.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/47963674120.pdfIn PDF document text
    • http://fk-fudosan.1nino3.com/app/webroot/img/userfiles/files/fativufivexexixer.pdfIn PDF document text
    • http://yao-cheng.com/uploadfiles/20210906073002.pdfIn PDF document text
    • https://anhhuynoithat.com/asset/files/22046765654.pdfIn PDF document text
    • http://torgoborud.org/images/file/45213208958.pdfIn PDF document text
    • https://dla-pracownika.pl/pliki_user/File/mitasokolafavibeb.pdfIn PDF document text
    • http://huiking.cn/uploads/file/090446439789.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161322fe5ee1db---98408532423.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=dream+league+mod+apk+2019PDF 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_off0000e9ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9AB 20168 bytes
SHA-256: ef341336b3c59a2e1f7ccedad9ee6595c7a49e5ad2075fb524298fd430ed27c0
font_01_sfnt_off00011e74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E74 10928 bytes
SHA-256: 6a17314596200c52be35ed4f1b31f3387506b76fe0f656366c1a086f8ee4e539
font_02_sfnt_off0001379c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1379C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1