Malicious PDF — malware analysis report

Static analysis result for SHA-256 2389eb62579fe2d5…

MALICIOUS

PDF

70.5 KB Created: 2021-09-09 15:02:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: d48fd4653b9c496336a17b0e59afb11b SHA-1: 4f632356da7860d85d7575c750e6c1fd34b0d632 SHA-256: 2389eb62579fe2d57b9d0b1e9cab32a617a5b127df4de9771ae8e376076ac686
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to other PDF files, indicating a link farm designed to host malicious content or phishing pages. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were directly extracted, the structure and embedded URLs are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://chv.vn/userfiles/file/14092401795.pdf In PDF document text
    • https://otterdisplay.com/userfiles/file/58182431160.pdfIn PDF document text
    • https://aecvfcom.nrgence.com/upload/userfiles/files/94415325054.pdfIn PDF document text
    • http://russia-ex.com/images/blog/file/9150237531.pdfIn PDF document text
    • http://gysanya.com/upload/file/210905220058924202l42rag6d4ay5.pdfIn PDF document text
    • http://soncongnghiepjotun.com/media/ftp/file/62200031730.pdfIn PDF document text
    • http://airzo.net/userData/board/file/4572633152.pdfIn PDF document text
    • https://vsetinrally.cz/userfiles/file/62170455185.pdfIn PDF document text
    • http://kasaitogo.com/uploads/files/wikanaro.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161395f5b75852---14319977668.pdfIn PDF document text
    • http://veoguidecostarica.com/ci/userfiles/files/99167725403.pdfIn PDF document text
    • https://maryamghiasi.com/images/upload/files/kufibazeki.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/afe0ada8946606446cea01dfaec1d69d/79784321384.pdfIn PDF document text
    • http://coaching-scolaire.net/userfiles/file/33359350700.pdfIn PDF document text
    • http://capitaloffice.pl/fotki/file/xezutori.pdfIn PDF document text
    • http://donaldnathanlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/157648904.pdfIn PDF document text
    • https://bhiringisamsankalimandir.org/ckfinder/userfiles/files/liratulosujeti.pdfIn PDF document text
    • http://orsini-blasioli.it/userfiles/files/jiwijajetesufutovi.pdfIn PDF document text
    • http://asdgolfclubtoscana.com/writable/public/userfiles/file/woxuvidexivabo.pdfIn PDF document text
    • http://avvocatoandreabruschi.it/userfiles/files/poxavapasanatusama.pdfIn PDF document text
    • https://maidintown.co.uk/wp-content/plugins/super-forms/uploads/php/files/2f3437ee3965fe832d510df910db8d7d/78447603185.pdfIn PDF document text
    • http://nazycakes.com/userfiles/file/99572312312.pdfIn PDF document text
    • http://khocabien.com/uploads/files/dizefazubolimigeta.pdfIn PDF document text
    • http://seamacros.com/upload/file/wotubufabapopamole.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=delete+everything+from+my+phonePDF 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_off0000b520.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB520 10656 bytes
SHA-256: 9f021bdf1f1be45d5bd9c5333d45948d28db2e1aae769949b41afdf09528de2f
font_01_sfnt_off0000cd52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD52 15480 bytes
SHA-256: 83941d08a948ee03c1825b3af5b418b767beac339fc6ebb02cee5bade3d3c033
font_02_sfnt_off0000f400.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF400 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1