Malicious PDF — malware analysis report

Static analysis result for SHA-256 273b9ecd58c38ffa…

MALICIOUS

PDF

83.4 KB Created: 2021-10-07 05:53:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 714e149f4b9eff6d68fc219d4b1b0cad SHA-1: ce0777eaf599ce142d912a61a66afd4552a645c1 SHA-256: 273b9ecd58c38ffa506f3b8b0f288c78d18026be6e418b62fb4118f07bbd36c4
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and ML classifiers indicated a high probability of maliciousness. The document contains numerous embedded URLs, many of which point to domains that appear to be part of a link farm, suggesting an attempt to direct users to potentially malicious content. The presence of a 'curl' command in the document text further indicates an intent to download or execute external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • LOLBin token sequence in document text high SE_LOLBIN_RUN_COMMAND
    Extracted document text contains a Windows script/execution tool name (PowerShell, mshta, cmd, rundll32, regsvr32, …) within 220 characters of a dangerous flag, command verb, or URL. This is a visible 'run this' instruction in HTML/PDF/RTF lure bodies, or — in macro-laden Office files — the macro's own string-pool entries appearing adjacent in extracted text.
  • 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://kaptenhoki.info/contents/files/16418696376.pdf In macro / runtime command snippet
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/74be34bd4a9cadf30c9283533f77da55/44200991426.pdfIn macro / runtime command snippet
    • http://www.accl-calibration.com/login/ckfinder/userfiles/files/kipiwuzupot.pdfIn PDF document text
    • http://jarosi.hu/files/file/kevexedaxi.pdfIn PDF document text
    • http://ukkies.be/userfiles/file/latetoxuworovotodutibezoj.pdfIn PDF document text
    • http://roberthalasz.eu/uploads/file/jexufazugexukokimotiz.pdfIn PDF document text
    • http://inercial.es/uploads/files/zibazupinir.pdfIn PDF document text
    • http://ferramentabelleggia.it/public/file/52978635432.pdfIn PDF document text
    • http://kondicionery-ivanteevka.ru/upload_picture/file/5176529338.pdfIn PDF document text
    • https://wonkingchina.com/d/files/tiloritej.pdfIn PDF document text
    • http://xn--80ab1a9a.xn--p1ai/sadm_files/3349491293.pdfIn PDF document text
    • http://timandlor.com/userfiles/file/21594249284.pdfIn PDF document text
    • http://wsp.pl/userfiles/file/13485832219.pdfIn PDF document text
    • https://pt-olympus.com/contents/files/69596467145.pdfIn PDF document text
    • http://ux-school.ru/files/files/51962380061.pdfIn PDF document text
    • http://xn--22cjbbm2eyae3ehabdb4kqdtae3dxnnc1fhf.com/user_img/files/rabuwiziwesanes.pdfIn PDF document text
    • http://dokumsuzgec.com/userfiles/files/35306504903.pdfIn PDF document text
    • https://kultmotor.virtualbodybuilding.hu/images/files/77397673215.pdfIn PDF document text
    • http://crosswaysrecruitment.com/userfiles/file/tikakozebewub.pdfIn PDF document text
    • https://rarahil.org.np/ckfinder/userfiles/files/15166338771.pdfIn PDF document text
    • https://iskoruma.com/upload/ckfinder/files/4792775328.pdfIn PDF document text
    • http://mabo-meccanica.eu/userfiles/files/75752339990.pdfIn PDF document text
    • https://wyslijpaczki.pl/app/webroot/files/userfiles/file/47765051645.pdfIn PDF document text
    • http://library.nesdb.go.th/ic/admin/ckfinder/userfiles/files/tazisokib.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=lying+cable+leg+curlPDF 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_off0000e1b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1B7 18320 bytes
SHA-256: 9cf3dc4bbc4bff78a11525daeb0708d14ba3f3fe60db76cb17e81e471124c7fe
font_01_sfnt_off000110fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012911.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12911 10332 bytes
SHA-256: 3a899ceed9a382305e42e804c53c5b5980505f7a1dc0e9998d57e463899ab56c