Malicious PDF — malware analysis report

Static analysis result for SHA-256 cac8197c58c9ad40…

MALICIOUS

PDF

68.0 KB Created: 2021-09-18 20:58:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: d96989290e35e7021a9885e9fa72912c SHA-1: ffdcbda5195e739d2aa5906754cedbb0ea5c56db SHA-256: cac8197c58c9ad40b4ae6297707d73e3cfa9a3b4fc8bc3d4706a23449410b56c
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to domains that appear to be part of a link farm designed to obscure the final destination. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior. ClamAV detection and ML classification further support its malicious nature, indicating it's likely a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 http://thermcom.cz/userfiles/file/gimonutagonizomejirolato.pdf In PDF document text
    • http://www.solarwindependence.com/ckfinder/userfiles/files/5928132423.pdfIn PDF document text
    • http://tradotel-riviera.com/file/61048219737.pdfIn PDF document text
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1613c0519e40cd---77285241865.pdfIn PDF document text
    • http://adirondackseafood.com/ckfinder/userfiles/files/61845629255.pdfIn PDF document text
    • http://cosmosimpex.com/app/webroot/ckfinder/userfiles/files/momowagisozepawunegemet.pdfIn PDF document text
    • https://rcvizovice.cz/ckfinder/userfiles/files/83760843126.pdfIn PDF document text
    • https://futuresbuilder.net/dayafter/uploadimages/newsimages/file/kizewugoxazafubekeno.pdfIn PDF document text
    • http://fittbikese.hu/files/file/puvarosupamanino.pdfIn PDF document text
    • https://argentinaproduct.com/ckfinder/userfiles/files/19793486456.pdfIn PDF document text
    • http://mwbright.com/upload_fck/file/2021-9-17/20210917200821788364.pdfIn PDF document text
    • https://semot.com/Store/userfiles/file/8353454433.pdfIn PDF document text
    • http://carmakers.cz/userfiles/files/67449854654.pdfIn PDF document text
    • http://onlineticketreview.com/images/file/56882839238.pdfIn PDF document text
    • http://agrion.org/upload/fichier/xiridajugezujitele.pdfIn PDF document text
    • https://www.cygnusdvlp.in/nitdurgapur/uploads/editorUploads/userfiles/files/56260574139.pdfIn PDF document text
    • http://amicalelaique-guyancourt.fr/ckfinder/userfiles/files/91343831679.pdfIn PDF document text
    • https://munis-roquesalbes.cat/demo/vilalba/imatges/file/wokezejeteset.pdfIn PDF document text
    • https://gtijsr.com/userfiles/file/19487399693.pdfIn PDF document text
    • https://fainitelecommunication.com/public/editorfiles/file/vowanitizi.pdfIn PDF document text
    • http://hotel-gerard-dalsace.com/upload/document/25962272616.pdfIn PDF document text
    • http://tamlaproject.com/userData/board/file/36544582460.pdfIn PDF document text
    • http://tianfonmm.com/d/files/6684244318.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=ttt+amino+acidPDF 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_off0000b0f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0F1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c908.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC908 10048 bytes
SHA-256: 14d8a3b6b83209c6ee6e8496bf885d961912e11667f9016ccb5ff51c1705de88
font_02_sfnt_off0000df55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF55 14424 bytes
SHA-256: 27a874225e414ecb9485fdcdae1bf4853251cf5871c4e2b19cd71fadd953f931