Malicious PDF — malware analysis report

Static analysis result for SHA-256 cac9de3ae724f0f3…

MALICIOUS

PDF

76.9 KB Created: 2021-09-20 18:58:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 3e02bedf8e8142d8fa8fc4ae4bb8ae54 SHA-1: d00756664c9aeb74984499b07e65097977bc2ca0 SHA-256: cac9de3ae724f0f36de2400dc2ac86b2ac7fa2041f760904f255505c9cacbd42
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of embedded URLs, many of which are on disposable hosting and appear to be part of a link farm, indicating a likely attempt to redirect users to malicious sites. The presence of external URIs and the overall structure suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://irlanc.ru/uplcv?utm_term=alfred+lesson+book+2+pdf PDF link annotation
    • http://thietkewebbacninh.com/webroot/img/files/darafos.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141102a73452---68870514095.pdfIn PDF document text
    • http://ellissi.org/userfiles/files/45493567667.pdfIn PDF document text
    • http://huarui-bio.com/upload/files/29482103232.pdfIn PDF document text
    • https://norservis.cz/files/files/nogelutuferunu.pdfIn PDF document text
    • http://gpsputhuppally.com/userfiles/file/73195183238.pdfIn PDF document text
    • http://cke.hk/userfiles/1766729236.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/gd6jab1vaq5m0ule7mi2lshk53/gafizotamimiwi.pdfIn PDF document text
    • http://www.bsa.by/ckfinder/userfiles/files/lekepokugov.pdfIn PDF document text
    • http://danguykhoidoanhnghiephp.vn/Upload/files/21703330288.pdfIn PDF document text
    • http://ateliergermain.club/sites/default/files/file/79007911373.pdfIn PDF document text
    • http://phone-server.com/userfiles/file/82673105029.pdfIn PDF document text
    • http://izumrud38.com/ckfinder/userfiles/files/xuxazekodimotozuvimufejo.pdfIn PDF document text
    • http://tingchucontrol.com/Uploadfiles/files/47274151993.pdfIn PDF document text
    • https://carlojans.com/cms/file/41619289777.pdfIn PDF document text
    • http://itps-group.com/uploadfiles/file/66183711001.pdfIn PDF document text
    • https://cometgroupinternational.com/ckeditor/ckfinder/userfiles/files/32813188534.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/bojirexokegodinum.pdfIn PDF document text
    • http://xn--z92bzy85x.com/userData/board/file/16456873066.pdfIn PDF document text
    • https://jordan.si/dokumenti/file/viwototidokujeri.pdfIn PDF document text
    • https://mtydizayn.com/userfiles/file/47972702698.pdfIn PDF document text
    • https://minhvuongthuphap.com/upload/ck/files/73713612764.pdfIn PDF document text
    • http://eikenhorstgroep.nl/userfiles/file/24004323769.pdfIn PDF document text
    • http://king-pro.com/userfiles/files/wujevanitusifekoxakifepud.pdfIn PDF document text
    • https://kurishupally.org/userfiles/file/94804835023.pdfIn PDF document text
    • http://smartraoptics.com/fck_filemanager_upload/file/12295885419.pdfIn PDF document text
    • 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_off0000c896.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC896 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e0ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0AD 10472 bytes
SHA-256: 7845c6042d91b4c842fe13e8f9f959a04c810d4fb435a3feacae77e069f3e188
font_02_sfnt_off0000f864.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF864 17520 bytes
SHA-256: fda4c17cb62840618edb35480a21af1ee5b2fea869e5e08c4261d224a457f748