Malicious PDF — malware analysis report

Static analysis result for SHA-256 a786565635d6c4c4…

MALICIOUS

PDF

73.4 KB Created: 2021-09-20 05:31:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 698c14f364328ed4752002d3533d792b SHA-1: 22b30c044353f3b250bce9aab46106eec67b13ff SHA-256: a786565635d6c4c45ad34beb82459acbb376fbef2dc0403618e97cde04b84a0a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious. It contains a large number of embedded URLs, many of which point to disposable domains, indicating a link farm designed to obscure the ultimate destination. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://editora-arara-azul.com.br/site/admin/ckfinder/userfiles/files/jewitizoruxeludo.pdf In PDF document text
    • http://graciaindoutama.com/kingkong/userfiles/files/jakuxilopulibavagufewiga.pdfIn PDF document text
    • https://vanphongphampmc.com/upload/files/xonavojafado.pdfIn PDF document text
    • http://aviatechinform.ru/sadm_files/vuwepuneto.pdfIn PDF document text
    • http://seowonbattery.com/files/fckeditor/file/1214081582613d82d70cfd8.pdfIn PDF document text
    • https://minjar.mebel18.com/uploads/files/39660876037.pdfIn PDF document text
    • https://www.naabelectric.com/userfiles/files/ruweworivofitetoluma.pdfIn PDF document text
    • http://ambcavallon.eu/userfiles/files/fijarumafafijojifok.pdfIn PDF document text
    • http://bjqyms.com/filespath/files/20210908092232.pdfIn PDF document text
    • http://www.mariabeckmann.com/fotos/uploads/files/zebubiminibibi.pdfIn PDF document text
    • http://brain-sh.tw/upload/file/zixujuf.pdfIn PDF document text
    • https://www.fyna.com.au/application/third_party/ckfinder/userfiles/files/77116714531.pdfIn PDF document text
    • http://saluteebenesseresas.it/userfiles/files/16993192348.pdfIn PDF document text
    • http://studiotecnicoforace.eu/userfiles/files/butadewaxinajum.pdfIn PDF document text
    • http://german-ex.com/images/blog/file/dunukesafagoputatafeka.pdfIn PDF document text
    • http://kustari.net/userfiles/file/6812762908.pdfIn PDF document text
    • https://khambenhxahoi115.com/images/files/46224888551.pdfIn PDF document text
    • http://studioarchterreni.it/userfiles/files/gizugi.pdfIn PDF document text
    • http://dolinakrzeptowa.pl/public/upload/ckfinder/userfiles/files/30291885012.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/30s7ckkud75h9vp2s3jkkqhf5s/258638748.pdfIn PDF document text
    • http://jysfh.com/upload_fck/file/2021-9-18/20210918061658590942.pdfIn PDF document text
    • http://dezmaster.com/userfiles/file/mixuwopubegarologufo.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/f8c0b813fdf7d7fd35d4da6fbf372f9e/dubexifopipemogimefazakub.pdfIn PDF document text
    • https://tailormade-sales-marketing.com/userfiles/file/79701134678.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=mod+apk+catsPDF 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_off0000bf55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF55 10116 bytes
SHA-256: c6d34f7d56fc3a9247a57c1e6622f963d467305d72a7cf458e4896751f56eb03
font_01_sfnt_off0000d617.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD617 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ee29.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE29 16272 bytes
SHA-256: 20447e6572c62f831f5cee52dcd391d2fecdb1160f33ee62e78fe684db11b755