Malicious PDF — malware analysis report

Static analysis result for SHA-256 817851b40640d12b…

MALICIOUS

PDF

70.7 KB Created: 2021-09-27 20:12:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 6aec6edf987c1ff05d4426a2761698ce SHA-1: 3139c09bf4aa2b0fcd2399be781273a33b247635 SHA-256: 817851b40640d12b840a0ecab685d83caeabf4672abd7f6d15bf0411f9009e9b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, with one heuristic identifying it as a link farm on disposable hosting. ClamAV detection and ML classification strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and external links suggest it's part of a spearphishing campaign aiming to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://valerart.com/ckfinder/userfiles/files/vozuwuwo.pdf In PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613cfefb65b54---22499954216.pdfIn PDF document text
    • http://anshan56.cn/userfiles/file/1631451281999524285.pdfIn PDF document text
    • http://kondicionery-domodedovo.ru/upload_picture/file/8649805328.pdfIn PDF document text
    • http://littlepearlspublishing.in/data/eimages/file/75524356858.pdfIn PDF document text
    • https://tonymusic.se/UserFiles/files/kibux.pdfIn PDF document text
    • http://taiwangallant.com/uploads/files/202109082001533179.pdfIn PDF document text
    • https://kitapkaplama.com/upload/ckfinder/files/boliwunonumamoguz.pdfIn PDF document text
    • http://miwon.vn/app/webroot/uploads/files/modose.pdfIn PDF document text
    • http://alfatreyd-mebel.ru/archive/images/file/gusuxodabatojulizadil.pdfIn PDF document text
    • https://imotrading.com/images/userfiles/34871442753.pdfIn PDF document text
    • http://phuvuongcorp.com/luutru/files/gidelof.pdfIn PDF document text
    • https://successstudio.net/userfiles/file/pipiwerulaleledig.pdfIn PDF document text
    • http://rococosofa.com/files/files/zakafoposo.pdfIn PDF document text
    • https://www.kadinlarsitesi.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614e0706461d2---72678195897.pdfIn PDF document text
    • http://igs.compcierge-asia.com/ckfinder/userfiles/files/xolif.pdfIn PDF document text
    • http://edituj.cz/res/file/ditegoditubizax.pdfIn PDF document text
    • http://www.elstar.ru/uploads/files/83456406100.pdfIn PDF document text
    • https://hram-uspeniya.ru/ckfinder/userfiles/files/2454561098.pdfIn PDF document text
    • https://www.almuhja.com/ckfinder/userfiles/files/gozarudajozutis.pdfIn PDF document text
    • http://toanthinh.vn/webroot/img/files/76416835996.pdfIn PDF document text
    • http://dgelc.com/userfiles/file/20210924163138.pdfIn PDF document text
    • http://saveondealz.com/ckeditor/ckfinder/core/connector/php/uploads/files/63492124302.pdfIn PDF document text
    • http://ingpoggi.eu/userfiles/files/54505623159.pdfIn PDF document text
    • https://daqing-jewelry.com/uploads/files/202109012346223292.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=evil+lands+online+action+rpg+apkPDF 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_off0000b3f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3F5 10832 bytes
SHA-256: 8dd5f90d13d5c95a3a4e6e13e98db8cc9bfcada78b8e54834fc92aa43d041c57
font_01_sfnt_off0000ccce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCCE 15752 bytes
SHA-256: 906ee8bf4ba0eb11bbac94ff90b067d85e9c7e0c84320f78cfbb8711ee1ca374
font_02_sfnt_off0000f4d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1