Malicious PDF — malware analysis report

Static analysis result for SHA-256 7e97c1e4756d1261…

MALICIOUS

PDF

69.5 KB Created: 2021-09-16 04:10:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 17252e437e76e6a2e3647b7dadc28e16 SHA-1: c6bb6282a3e8542b6b3d3c752889731c72ad3c8c SHA-256: 7e97c1e4756d12613c79acfaf70de581996593b69960d0752de860246607bf63
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to potentially malicious content. The document body is heavily obfuscated and contains metadata suggesting it was generated by wkhtmltopdf, a tool often used to create PDFs from web content, which aligns with the link farm behavior.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://naim.naparts.com/images/fck/file/61708652574.pdf In PDF document text
    • https://burgaseguros.com/userfiles/file/nozodidateganudunofa.pdfIn PDF document text
    • http://aadcnfgl.netsociality.com/upload/files/posuf.pdfIn PDF document text
    • http://2013.letnifestiwal.pl/ckfinder/userfiles/files/pojug.pdfIn PDF document text
    • http://liccuza.ro/stiri_files/file/16914432389.pdfIn PDF document text
    • http://www.novosib-sport.ru/ckfinder/userfiles/files/73370483579.pdfIn PDF document text
    • http://lso-msm.com/userfiles/file/46539008448.pdfIn PDF document text
    • https://beta.nhatthiengroup.com/files/uploaded/files/62710013670.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/vemapijozawuzabemiga.pdfIn PDF document text
    • https://jingchengs.com/jingchengs/ckfinder/files/20210903223015.pdfIn PDF document text
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/1ff1167dca5174a7a0e2310f555b8b48/rolafitexigubo.pdfIn PDF document text
    • https://chilegastronomia.cl/uploads/userfiles/files/mapovebesipuxulukadas.pdfIn PDF document text
    • http://elai.kz/upload/2021/09files/210912175303607495674ax.pdfIn PDF document text
    • http://opuspointpartner.com/ckfinder/userfiles/files/zigos.pdfIn PDF document text
    • https://dhesient.com/media/84834749503.pdfIn PDF document text
    • http://progettocecinacuore.it/writable/public/userfiles/file/72021111569.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613aff8f1ca8a---7022559833.pdfIn PDF document text
    • http://xn----7sbjvweekof5d.xn--p1ai/files/files/ramoxa.pdfIn PDF document text
    • http://grandfiltr.com/files/file/rilodarumapanozawifopej.pdfIn PDF document text
    • http://leicesterbiketec.com/userfiles/file/88345378574.pdfIn PDF document text
    • https://nutricount.cz/UserFiles/File/pidotobajasug.pdfIn PDF document text
    • https://www.domaine-boussard-chablis.fr/ckfinder/userfiles/files/46757651448.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/27073296282.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=the+book+of+mirdad+in+tamil+pdf+free+downloadPDF 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_off0000b086.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB086 15552 bytes
SHA-256: bf114977f228cb6f739f9ac89e42f9aa958af7dcef12c8be23279386a3c4bde4
font_01_sfnt_off0000d6f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ef0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF0F 10876 bytes
SHA-256: ac93c634ffff531d9e9ba933a90788bf5656df2c7ff83d7ab19c77029ca9792a