Malicious PDF — malware analysis report

Static analysis result for SHA-256 9390c54b8c364b5b…

MALICIOUS

PDF

82.6 KB Created: 2021-09-22 16:17:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 2d8001c12cb6aef5fb1dc57e32fda9a6 SHA-1: 94e706022805c6e5ebdd725f76022ed474af3801 SHA-256: 9390c54b8c364b5b52870d02429e056d5706c8d85436d8266b27e0002565b961
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1539 Steal Application Data

The file was flagged by multiple heuristics, including ML classification and a specific rule for MFA/one-time-code harvesting lures, indicating a credential phishing attempt. The presence of numerous embedded URLs, many pointing to potentially disposable domains, further supports this. Although no scripts were explicitly extracted, the PDF structure and the nature of the lure suggest it is designed to trick users into providing sensitive authentication information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • MFA / one-time-code harvesting lure high SE_MFA_LURE
    Document asks for a one-time code, authenticator approval, or MFA confirmation — consistent with credential phishing kits that steal session tokens or abuse multi-factor authentication
  • 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://toskov-yordanov.com/userfiles/file/70547661722.pdf In PDF document text
    • http://electriccityusa.com/images/fck_uploads/file/74892530898.pdfIn PDF document text
    • http://mn-print.ru/ckfinder/userfiles/files/48310307397.pdfIn PDF document text
    • http://vinhhangvien.com/upload/files/niviluropize.pdfIn PDF document text
    • http://ashioke.com/images/library/File/nofujatunubuvekudawaxuwal.pdfIn PDF document text
    • http://clearspace-design.com/CKEdit/upload/files/zexijesaxuwatomuwevomat.pdfIn PDF document text
    • http://helder-effect.nl/userfiles/file/35301075599.pdfIn PDF document text
    • https://fallsplat.se/bildbank/file/kawutawo.pdfIn PDF document text
    • https://sanipacific.com/attachment/file/43975957687.pdfIn PDF document text
    • http://ingmontagna.com/userfiles/files/33559930773.pdfIn PDF document text
    • https://toppelletmachine.com/d/files/jorov.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b11e6ef04e---xatogujorazo.pdfIn PDF document text
    • https://amd-export.com/site/upload/file/41395102384.pdfIn PDF document text
    • http://image.dlib.vn/libedu/news/bachviet/20210916/file/84207123567.pdfIn PDF document text
    • http://terezmisszio.eu/files/file/64501141218.pdfIn PDF document text
    • http://archiw.bibliotekalesmierz.eu/img/upload/files/91968969558.pdfIn PDF document text
    • http://solee.cn/ckfinder/userfiles/files/87734890094.pdfIn PDF document text
    • https://fotofidelity.cz/userfiles/file/beguvedodel.pdfIn PDF document text
    • http://buzmakov-ua.ru/admin/ckfinder/userfiles/files/97036447778.pdfIn PDF document text
    • http://thsport.dk/ckfinder/userfiles/files/siwapopuwogebaxuzijowefux.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/1b123477ce0d5826491511eeafcad3a4/23671720039.pdfIn PDF document text
    • https://linhngapt.vn/upload/files/zasoxololop.pdfIn PDF document text
    • http://duocthientam.com/uploads/ckfinder/files/5791566719.pdfIn PDF document text
    • https://mariapolis.net/ckfinder/userfiles/files/sadijasutepizazup.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=delete+google+accounts+on+androidPDF 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_off0000df03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF03 10648 bytes
SHA-256: c45f9dd086970202082f34d4d1a00ede4914125ad1377b79afaa1c5f5cdb5f88
font_01_sfnt_off0000f74e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF74E 17592 bytes
SHA-256: 3af28cb93ea273e1912eb8d35a30ba551de1b5e79a499689ee5e564798736e01
font_02_sfnt_off0001242e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1242E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1