Malicious PDF — malware analysis report

Static analysis result for SHA-256 e3f10d7f2b4f8d89…

MALICIOUS

PDF

83.4 KB Created: 2021-09-10 05:15:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 903a86aa4a798b7b6cabbc21d7a885a5 SHA-1: 87b5835c04ec781d81179c286d4affdb99433c38 SHA-256: e3f10d7f2b4f8d8954957c49ef5d5cb5e2911d018a3469db67bf40859b7dc8a8
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to suspicious domains and are structured as a link farm, a common tactic for distributing malware or conducting phishing campaigns. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a deliberate attempt to obscure the final malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://sindikat777.ru/ckeditor/ckfinder/core/connector/php/uploads/files/lobogusitomirogusota.pdf In PDF document text
    • https://padservhosting.com/userfiles/file/vuzizanakivo.pdfIn PDF document text
    • http://www.mariabeckmann.com/fotos/uploads/files/76547913923.pdfIn PDF document text
    • http://stroytehcentr.ru/images/file/nodajevofajuzo.pdfIn PDF document text
    • http://csc0535.com/userfiles/file/20210910014441_63kjx5.pdfIn PDF document text
    • https://ehlibeytalimleri.com/resimler/files/xagijolidulekojimaxejok.pdfIn PDF document text
    • https://happycolaborativo.com/uploads/files/tidolelu.pdfIn PDF document text
    • https://rallstarawards.us/nbloom/fckuploads/file/waxurikoduzelenevugarumal.pdfIn PDF document text
    • http://huijingweb.com/upload_fck/file/2021-9-10/20210910005618873275.pdfIn PDF document text
    • https://isagrinio.gr/userfiles/44501322700.pdfIn PDF document text
    • http://reklama-kemerovo.ru/files/files/74152850568.pdfIn PDF document text
    • http://pretaporter-pegah.com/userfiles/file/pilupufomefataxu.pdfIn PDF document text
    • http://neonatal-surgery.ru/userfiles/files/tovugusobega.pdfIn PDF document text
    • https://bentzendesign.se/wp-content/plugins/formcraft/file-upload/server/content/files/16139f6a0104f3---28727354556.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131dbcadef64---71735885291.pdfIn PDF document text
    • http://wawa757.com/uploads/files/wuwiru.pdfIn PDF document text
    • http://j1ent.com/userfiles/file/20210909065146.pdfIn PDF document text
    • http://kechengchem.com/upload/files/xagebosulaf.pdfIn PDF document text
    • https://kemxoi.vn/app/webroot/files/images/pages/files/duxazapamaterebogoxi.pdfIn PDF document text
    • https://777mto.info/contents/files/radenujero.pdfIn PDF document text
    • http://cerritos.songhakbbq.com/uploads/files/8522980426.pdfIn PDF document text
    • https://spirit-legend-enterprises.com/webroot/editor-uploads/files/rilimepimeseme.pdfIn PDF document text
    • http://xn----7sbicwad4afgcgd5aph7d5e.xn--p1ai/ckfinder/userfiles/files/redotigosapija.pdfIn PDF document text
    • http://www.klimavill.com/data/editorfile/66025744857.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=android+copy+part+of+smsPDF 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_off0000de79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE79 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f68b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF68B 18556 bytes
SHA-256: 762589248e6158ddee3cbd672004a494c4a89828d3b8d5573e4a3ac50441f483
font_02_sfnt_off0001273e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1273E 10700 bytes
SHA-256: f080607dfa2dceaad08bc76995b47efb3a2f20a6f55ae1c3ea8b8772ef6afbd8