Malicious PDF — malware analysis report

Static analysis result for SHA-256 f66c2c94b4bda525…

MALICIOUS

PDF

75.1 KB Created: 2021-09-25 23:20:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 58f22da9f149f3e49ba9687212aa5987 SHA-1: 076405a435850c5c914f203d85f72fa9c05e8f96 SHA-256: f66c2c94b4bda525654bc1f44eb1641942c2c887e8a6c83913265616b3a01f98
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous external URIs pointing to various domains. The document body is heavily obfuscated, preventing a clear understanding of its direct content, but the presence of many distinct, disposable-hosting domains suggests a phishing or malware distribution scheme. No scripts were extracted, but the PDF structure itself is leveraged to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 https://archism.ru/uplcv?utm_term=samsung+a40+vs+iphone+7 PDF link annotation
    • http://glina-master.ru/admin/ckfinder/userfiles/files/nuzatega.pdfIn PDF document text
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/92934355025.pdfIn PDF document text
    • https://mobiligennari.com/userfiles/file/finorigas.pdfIn PDF document text
    • https://sieuthimaytinhcu.vn/upload/files/37146589885.pdfIn PDF document text
    • http://inica.org/files/file///53521575723.pdfIn PDF document text
    • https://kiemtoandongnghi.com/public/plugins/ckfinder/userfiles/files/bagusasepegonorokexejeb.pdfIn PDF document text
    • http://www.aportecnica.com/imagenes/editor/file/katuvivot.pdfIn PDF document text
    • http://yuemeism.com/uploadfiles/files/dijizepunonatupobotalima.pdfIn PDF document text
    • http://solis.altrodesign.eu/ckfinder/userfiles/files/42764405269.pdfIn PDF document text
    • http://jumpstart.mobi/ckfinder/userfiles/files/wupunolupume.pdfIn PDF document text
    • https://www.ksmt.edu.np/assets/ckfinder/userfiles/files/65789364373.pdfIn PDF document text
    • http://www.medicellbank.com/userfiles/files/wunod.pdfIn PDF document text
    • http://eraldocomo.it/userfiles/files/tegolobedulivoworidor.pdfIn PDF document text
    • http://sahrugs.com/userfiles/file/24289823653.pdfIn PDF document text
    • https://trouver-une-ssii.com/img/pics/files/sofubi.pdfIn PDF document text
    • http://szentdorottyapatika.hu/files/modezumiv.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/55707458372.pdfIn PDF document text
    • https://rlmahtani.com/userfiles/files/vatukexot.pdfIn PDF document text
    • http://sydjpg.com/images/upload/file/20210908_044708_127.pdfIn PDF document text
    • https://pilot-nav.com/ckfinder/userfiles/files/ruwovaki.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f967706f57---belisabutuloluf.pdfIn PDF document text
    • https://www.prowallpanama.com/wp-content/plugins/super-forms/uploads/php/files/727897f6003f0abdf752bba13e820567/46656206960.pdfIn PDF document text
    • http://kerekesvillszer.hu/UserFiles/file/nibawutu.pdfIn PDF document text
    • https://supermagnum-bg.com/ckfinder/userfiles/files/39165838074.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_off0000b8a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8A9 10948 bytes
SHA-256: f09c138273acc4aa5f925a84d5bf9569f1d37ede1241895696ee69ddf44459f9
font_01_sfnt_off0000d1e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1E8 20688 bytes
SHA-256: f82fcf36c070c6fbb77d713664eade96395080d21297ccd4a460ae7ae128e467
font_02_sfnt_off000106f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1