Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e52c22ef0fafc94…

MALICIOUS

PDF

82.9 KB Created: 2021-09-18 20:57:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: efcae993f552f2a3ed69b3bebda0a3d2 SHA-1: fb9a709c0838cca4ace004aa1d036e2f1674cfd8 SHA-256: 8e52c22ef0fafc9423ebddbf5417c873c31ecf6ff614f66a3e765cfe6f8d3986
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites acting as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to phishing or malware distribution sites. The presence of external URIs and link farms suggests an attempt to direct users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/pot5mhaj1spc66o0ap3pir3pe2/15375443232.pdf In PDF document text
    • https://coffotea.com/uploads/files/202109170937131307.pdfIn PDF document text
    • https://regenerateacademy.com/file/55035745757.pdfIn PDF document text
    • http://lsphc.com/userfiles/file///91198675769.pdfIn PDF document text
    • http://thaicockstar.com/ckfinder/userfiles/files/40890966656.pdfIn PDF document text
    • http://gz-chengeng.com/uploadfile/files/wenafoxibo.pdfIn PDF document text
    • http://interno-kazan.ru/upload/files/zifoditurala.pdfIn PDF document text
    • http://mapect.com/upload/fckeditor/file/xugokelub.pdfIn PDF document text
    • https://parklanehotel.asia/userfiles/file/kudumoxirovakofuvo.pdfIn PDF document text
    • http://vizugy.hu/uploads/files/vavevimazujozupenukat.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161437c51492cc---48459873442.pdfIn PDF document text
    • http://the100voicesofgospel.ch/fichiers/newsletter/file/vofer.pdfIn PDF document text
    • http://jarosi.hu/files/file/vemekozutedulij.pdfIn PDF document text
    • https://vestol.bg/files/file/31780825504.pdfIn PDF document text
    • http://signauction.net/userfiles/file/33415735640.pdfIn PDF document text
    • http://etcpremium.com/userfiles/files/tosezakurux.pdfIn PDF document text
    • https://biocoop.legreniervert.fr/ckfinder/userfiles/files/ponuwedipururano.pdfIn PDF document text
    • https://namkhoasaigon.vn/web/images/files/xujabuzaju.pdfIn PDF document text
    • http://bk-plus.at/userfiles/files/17182893503.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/lc5i0tk8godsce3mts8cn50gd2/61531392519.pdfIn PDF document text
    • https://lmetinternationalschool.in/ckeditor/ckfinder/userfiles/files/dewazefupoxinebe.pdfIn PDF document text
    • http://pusheng168.com/uploadfiles/20210901122928.pdfIn PDF document text
    • http://problemconsulting.com/img/download/files/70687145654.pdfIn PDF document text
    • http://atanasijornet.net/uploads/ckfinder/files/22453960789.pdfIn PDF document text
    • https://fedico.ca/upload/editor/file/welemenusazukunarilokedu.pdfIn PDF document text
    • http://gelateriacool.it/userfiles/files/30110518543.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=five+nights+at+freddy%27s+multiplayer+onlinePDF 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_off0000dd88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD88 17756 bytes
SHA-256: c89b0749eda7fc646ed938940a6074cdadb830d22208cb802e5094685b59daf3
font_01_sfnt_off00010b8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B8A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000123a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123A1 11236 bytes
SHA-256: 494966388fcbb25880f59a28bee85efbdaea99c4764e59ac6e83edc5ea95be43