Malicious PDF — malware analysis report

Static analysis result for SHA-256 c95eb9cfe8abaaea…

MALICIOUS

PDF

98.8 KB Created: 2021-09-18 23:04:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: f63005a416a352f5364e8aa5a39d5667 SHA-1: d6a8800143b340175b5278ca80c344e23f724553 SHA-256: c95eb9cfe8abaaea7ca2a9d3e9c8690ab0b73467e62885af127973fede977b23
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. The heuristic 'SE_FAKE_CAPTCHA' suggests the document attempts to trick the user into executing commands or pressing keyboard shortcuts by displaying a fake CAPTCHA. Embedded JavaScript streams are present, likely used to facilitate the malicious payload delivery. The document also contains numerous external URIs, many of which point to potentially malicious PDF files.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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://perechen-izdaniy.ru/js/ckfinder/userfiles/files/susotetasub.pdf In PDF document text
    • http://htbestcomputer.com/media/ftp/file/nabexodigupub.pdfIn PDF document text
    • http://gz-theoutfit.com/UploadFiles/FCKeditor/20210901195409.pdfIn PDF document text
    • http://teplo76.ru/uploads/file/53650139412.pdfIn PDF document text
    • http://grabnerestriche.at/sigam.pdfIn PDF document text
    • https://pgprojekt.pl/Upload/file/99890258054.pdfIn PDF document text
    • http://evohome.pl/userfiles/file/zexamesesodatoxikigek.pdfIn PDF document text
    • http://meteosputnik.ru/userfiles/file/78827815361.pdfIn PDF document text
    • http://tsyrulnikov.ru/upload/file/19965087629.pdfIn PDF document text
    • https://ozora.schaffsen.com/contents/file/lagezitafubetodosigare.pdfIn PDF document text
    • http://meditopthailand.com/file/wuvuribexatozixaboroxelon.pdfIn PDF document text
    • http://fsanaq.com/upload/file/210918034846966501vgxnd0yb50zs.pdfIn PDF document text
    • http://studiotecnicomaglio.it/userfiles/files/47069007124.pdfIn PDF document text
    • http://jobsandhi.com/uploaded_files/userfiles/files/xosovijewebinumitepu.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/16144b06dc9884---gisobesosetugokiboreg.pdfIn PDF document text
    • http://kbcsisa.com/upload/fckeditor/file/josifibusajewegalenejozen.pdfIn PDF document text
    • https://ataru.site/js/ckfinder/userfiles/files/rirulunonu.pdfIn PDF document text
    • https://giverny-bkk.com/upload/files/11755620192.pdfIn PDF document text
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/80490141302.pdfIn PDF document text
    • https://webmenuplus.com/images/file/34443166015.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/2q3a6fa66acen59cu4mrcbndkj/84034745862.pdfIn PDF document text
    • http://smolninskayahotel.com/userfiles/file/perozofamukigiso.pdfIn PDF document text
    • https://pre-www.bridge-college.com/uploaded/ckeditor/files/25067203405.pdfIn PDF document text
    • https://eletvital.hu/uploads/files/82361765234.pdfIn PDF document text
    • https://dutchfansitenetwork.nl/ckfinder/userfiles/files/21969829612.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=v+bucks+generator+switchPDF 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_off0001164c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1164C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00012e63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E63 10852 bytes
SHA-256: a1974b8571e197b7c16338b6d471f77ff1e7ef49d5d5a671952a93636df75cdf
font_02_sfnt_off00014785.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14785 20248 bytes
SHA-256: ec5e6924e5900f3b05c5f84036bce91dd8aa8d901a5a9017d855d09eeda3358c