Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa550fba7f0142e5…

MALICIOUS

PDF

82.8 KB Created: 2021-09-22 18:29:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 0d0a91fe5359713dfb450e6bfd839fe4 SHA-1: 9ba374d8218ee791c6bdf5489b6621569f42d6f4 SHA-256: aa550fba7f0142e5b950d0d74acfd58eb18928658d1e58e28fbe1babc233de56
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm on disposable hosting, with numerous embedded URLs pointing to potentially malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically flags this as a tactic for distributing malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://berettyotv.hu/userfiles/files/zetobadupifufesogirepow.pdf In PDF document text
    • http://resurrection-life.net/userfiles/files/84962103501.pdfIn PDF document text
    • http://educasters.co/ckfinder/userfiles/files/nekekewetixalutipon.pdfIn PDF document text
    • http://savages.lu/imagesRTE/files/gekonofufebarofenuk.pdfIn PDF document text
    • https://steammining.com/userfiles/file/78226615407.pdfIn PDF document text
    • https://www.artikel238.nl/emmwebbit/resources/ckfinder/userfiles/files/27299510115.pdfIn PDF document text
    • https://ikomsolutions.com/admin/userfiles/file/fexoba.pdfIn PDF document text
    • http://daearesort.com/FileData/ckfinder/files/20210918_BFDDF98B286D6FB1.pdfIn PDF document text
    • http://dichvumucin.com/upload/ckupload/files/raroduzodijigujo.pdfIn PDF document text
    • http://meimagedance.tw/ufiles/files/bakerobadanakugisir.pdfIn PDF document text
    • http://www.mueblesgamez.com/ckfinder/userfiles/files/86805813892.pdfIn PDF document text
    • http://xn--82cac8d3ajrc0gd0bo4a7nf3qg.com/userfiles/files/72627750595.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/f91c3e4f02c05f3fd1d549f7d9f4d123/99093333809.pdfIn PDF document text
    • http://ricettebiagi.it/uploads/assets/file/7621322010.pdfIn PDF document text
    • http://esenkardeslerinsaat.com/resimlerfiles/26826137157.pdfIn PDF document text
    • https://mariapolis.net/ckfinder/userfiles/files/18824323208.pdfIn PDF document text
    • http://kiszelyugyvediiroda.hu/docs/file/32228028032.pdfIn PDF document text
    • https://asoriofrio.org/ckfinder/userfiles/files/lunibevomegetukad.pdfIn PDF document text
    • http://oguzlarotomatiksanziman.com/depo/sayfaresim/file/fetapikodibima.pdfIn PDF document text
    • https://kozlovka.mebel18.com/uploads/files/ledaludaroruxowuvino.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16144b98527da9---82117508380.pdfIn PDF document text
    • https://abisspaandboutique.com/nbloom/fckuploads/file/nivujipizexugi.pdfIn PDF document text
    • http://interiorconsignments.com/media/file/gibozeketeg.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=system+tools+android+all+in+one+toolboxPDF 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_off0000e110.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE110 10840 bytes
SHA-256: dbf75be303df9956f6cb3688f644177a91a6fa7218cf6a0161ee7d859d02ac69
font_01_sfnt_off0000fa0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA0D 16792 bytes
SHA-256: 36c005c4963b6955608c8921918ddd244f9caf619bcb47598f501f1a3b132a6c
font_02_sfnt_off00012559.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12559 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1