Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b396331ce07ea65…

MALICIOUS

PDF

73.6 KB Created: 2021-10-02 11:54:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 24f079c092ea5fee0f8c9c780a1888c4 SHA-1: 692c99f7be948fbafa40337fd6d32981a3d85e10 SHA-256: 1b396331ce07ea6537da31365bc9083aff2ef5ccb971aa00b58c295b9a85fca1
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs pointing to other PDF files hosted on compromised websites. This suggests a phishing or malware distribution scheme, where users are lured to click on links that lead to further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/7d23507c957ee00d5de7883db79a5477/ketasulupirujuzavawabuzi.pdf In PDF document text
    • https://elesud.it/img_pagine/file/88923939514.pdfIn PDF document text
    • https://tonycustomtailoring.com/nbloom/fckuploads/file/12393308449.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/3cf38cde74337286a93bd0eb539d203c/56281715062.pdfIn PDF document text
    • http://saipanbooking.com/FileData/ckfinder/files/20210929_B5BE733D5C68489F.pdfIn PDF document text
    • http://chilepools.com/contents/files/risekemigefujedijupidoda.pdfIn PDF document text
    • http://strategie-online.net/catalogue_dynamique/file/11565325981.pdfIn PDF document text
    • https://miraclechuppahs.com/userfiles/file/93542915332.pdfIn PDF document text
    • https://fotobolfestmeny.hu/mvc/userfiles/file/21148456931.pdfIn PDF document text
    • https://karolinanowak.com/userfiles/file/nimusopufesaxokuvopokevat.pdfIn PDF document text
    • https://www.lire-les-notes.com/ckfinder/userfiles/files/92532869346.pdfIn PDF document text
    • http://madinagirls.com/easydo%20v2.00/files/uploads/80747825816.pdfIn PDF document text
    • https://www.multilandtours.com/assets/ckfinder/userfiles/files/farakoparolizerufu.pdfIn PDF document text
    • https://kstraders.com/userfiles/file/tugikiked.pdfIn PDF document text
    • http://phongkhamthienhoa.org/images/files/jigurinurel.pdfIn PDF document text
    • https://sankaibearing.com/userfiles/files/67129982705.pdfIn PDF document text
    • https://8-hi.dataroom.tw/upload/file/zozawarirezoju.pdfIn PDF document text
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/060ugqgtg2neingecl6vg1925i/jubidunuzejin.pdfIn PDF document text
    • https://pecsikult.hu/files/file/53397170452.pdfIn PDF document text
    • http://www.ujepites.hu/userfiles/files/nokikezuvaruxa.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/vumubavoterarakanitoxowas.pdfIn PDF document text
    • http://www.juniorcollege.cl/ckfinder/userfiles/files/63030891515.pdfIn PDF document text
    • http://worldofpacifiers.com/editor_uploads/system/files/tumekotewunivaxedo.pdfIn PDF document text
    • http://tumakuruvoice.com/tumkurvoice/ckeditor/ckfinder/userfiles/files/40854139903.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612eb61ad64dc---vukozusabaluk.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=40+years+of+togethernessPDF 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_off0000bb63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB63 10572 bytes
SHA-256: b0ac5155f3248f439dbfd8e0ba49882c1ca5fe561c78a1e1ca25642a3994de8b
font_01_sfnt_off0000d385.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD385 17740 bytes
SHA-256: 28937872d8c1de88757e0f6fbc41278a2354400d4277ff3ff81c112dafc9aabe
font_02_sfnt_off000100f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1