Malicious PDF — malware analysis report

Static analysis result for SHA-256 28652063a8a69c53…

MALICIOUS

PDF

81.4 KB Created: 2021-09-19 01:26:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 1eecbd0c401b53bdeeee093d4c42312e SHA-1: b4e643023debeed5894453bac770a14512cfac53 SHA-256: 28652063a8a69c532e36435be48133155f01777ef7750a32f1a4753f1fdc7b87
206 Risk Score

Malware Insights

MITRE ATT&CK
T1059 Command and Scripting Interpreter T1566.001 Spearphishing Attachment

The PDF contains heuristics indicating it is a link farm and attempts to lure users into executing commands via their clipboard. This suggests the document is designed to facilitate the download and execution of a second-stage payload. The ClamAV detection and ML classifier further support its malicious nature, likely as a phishing or trojan delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • Clipboard command execution lure high SE_CLIPBOARD_COMMAND_LURE
    Document tells the user to copy or paste clipboard content into Run, PowerShell, cmd, or another shell-like execution context
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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 http://usefchina.com/uploadfile/file///2021091804474977.pdf In PDF document text
    • https://ladychief.com/wp-content/plugins/super-forms/uploads/php/files/e06f98d2f36b8753d05cbef84efd0acb/safipujutetadibetor.pdfIn PDF document text
    • https://rhuyscampingcar.fr/images/files/wexopenaniratosudevi.pdfIn PDF document text
    • http://fitviewer.de/files/file/31842989399.pdfIn PDF document text
    • http://marisqueandopremios.com/campannas/file/foxexinipij.pdfIn PDF document text
    • http://balbu.eu/uploads/news/file/93634247092.pdfIn PDF document text
    • http://portalcom-b2b.es/img/user//file/_0245565001631085815.pdfIn PDF document text
    • http://sarigol.kr/userData/ebizro_board/file/60160533979.pdfIn PDF document text
    • http://steinemann-ag.ru/31096159525.pdfIn PDF document text
    • http://becskeicsodajo.hu/admin/fck_upload/file/wuridipotoxosi.pdfIn PDF document text
    • http://adbuilder.at/ckfinder/userfiles/files/27719173077.pdfIn PDF document text
    • https://agros.net/uploads/file/23515787547.pdfIn PDF document text
    • http://tuecpa.com/file_media/file_image/file/fopuwuponenirezemaxes.pdfIn PDF document text
    • http://smarttechsolutionukltd.com/uploaded_files/userfiles/files/79413822791.pdfIn PDF document text
    • http://njxinbell.com/upload/files/zalajomomineka.pdfIn PDF document text
    • https://linhquan-group.com/upload/ck/files/40479756393.pdfIn PDF document text
    • http://worshipedia.mobi/sites/default/files/file/bojixekugexadunipu.pdfIn PDF document text
    • https://crmsaas.dswip.com/ci/userfiles/files/27261713084.pdfIn PDF document text
    • http://strahyi.ru/images/file/52582333025.pdfIn PDF document text
    • http://everest-c.ru/ckfinder/userfiles/files/xebodon.pdfIn PDF document text
    • http://hflbdq.com/uploads/file/130048292030.pdfIn PDF document text
    • https://talenthunt.biz/userfiles/file/wupasaj.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/161460756a9905---jobizirexixolujar.pdfIn PDF document text
    • http://sushistoryus.com/uploads/files/lovune.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=forgot+pdf+password+without+softwarePDF 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_off0000da4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA4E 17068 bytes
SHA-256: 3477e2df56a15435ae3a91a39db099be0052b0f75b048718c3ab6c115f333ea5
font_01_sfnt_off000106b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106B0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011ec7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EC7 10788 bytes
SHA-256: 00f79c9dc61b053ca27faca60acfe83116485d74b4991a3968a5a4c39c41394c