Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b416e4fddb9c94e…

MALICIOUS

PDF

78.8 KB Created: 2021-09-18 21:23:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7139f4db5b56ee982fdc4ff956f771f6 SHA-1: 0171747fd938edffd53972de69c1f10612d15f75 SHA-256: 3b416e4fddb9c94e91a4726761083e1161479b52b7cc4fb271d4a72c661f823c
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains an embedded JavaScript stream and a link farm with numerous external URIs, suggesting an attempt to redirect users to malicious content or download further payloads. The presence of JavaScript points to an execution vector, likely for downloading and executing a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://ymjgolf.com/file_media/file_image/file/89829160221.pdf In PDF document text
    • http://doctour.hu/uploads/ckfinder/userfiles/files/zuxorelejubijabimejovim.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/16140bfa1091ab---sawofewakeduwefagulobi.pdfIn PDF document text
    • http://china-hold.com/UploadFile/file/20210909201055431.pdfIn PDF document text
    • https://officialbacknumber.com/editor_up/difilokexa.pdfIn PDF document text
    • https://ceccarbotosani.ro/userfiles/file/51401632563.pdfIn PDF document text
    • http://m-styleauto.com/js/upload/files/subewigirojefa.pdfIn PDF document text
    • http://puntolinea.org/userfiles/files/83388239858.pdfIn PDF document text
    • http://alibabashipping.com/userfiles/file/84849385255.pdfIn PDF document text
    • https://maria-galland.ru/files/file/64565171530.pdfIn PDF document text
    • http://metallpress.ru/files/ronodine.pdfIn PDF document text
    • http://phukhoabacninh.com/images/files/34971739037.pdfIn PDF document text
    • http://www.childofafrica.org/media/userfiles/file/zimewefiwo.pdfIn PDF document text
    • http://mfo-fond.ru/ckeditor/ckfinder/userfiles/Images/files/paladotokokujefa.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/490c38fe99fed0406850677f7d5d6b89/79283940976.pdfIn PDF document text
    • http://recrute.fr/files/files/52043465461.pdfIn PDF document text
    • https://luminex.pl/upload/file/jotogusiwujezim.pdfIn PDF document text
    • http://hoteldanang.com/uploads/images/files/dinoletasuwixud.pdfIn PDF document text
    • http://gr-chem.com/upload/files/bofojovepajipimazasav.pdfIn PDF document text
    • http://smartdeal.pl/files/upload/files/65484950940.pdfIn PDF document text
    • https://standsimulator.com/ckfinder/userfiles/files/tezagipukijefubopalozated.pdfIn PDF document text
    • https://seas2010.cienciaevida.pt/site/upload/file/mokumizobukipemepamevila.pdfIn PDF document text
    • http://dulwichtaxi.com/survey/userfiles/files/wefasoseve.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=among+us+god+mode+apkPDF 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_off0000cf69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF69 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e77b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE77B 17752 bytes
SHA-256: 82716daf4417b3cad5007227c81706df67e7f90b1c8ba5d5c16a6724f4551cbc
font_02_sfnt_off000115a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115A5 10572 bytes
SHA-256: 1bff38734ba2480be8ec19dba62583e609886e7c67884a2a2ce8e0a7dd0de550