Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5be50235c3fa1bd…

MALICIOUS

PDF

80.6 KB Created: 2021-09-16 09:43:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 614befb0ce245b8d72a159bdd1aef64c SHA-1: ca0fbd054ee5b07e9abf76075ff914848f3b1800 SHA-256: f5be50235c3fa1bd0f00941ca401debd1d86c0ddbd473aaec260e24dbf5681ad
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous external links, many pointing to unknown domains, suggests a link farm designed to redirect users to potentially harmful sites. While no scripts were explicitly extracted, the PDF structure and link farm heuristic point towards a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://vico-immobilien.com/ckfinder/userfiles/files/65783527104.pdf In PDF document text
    • https://jotekonybakterium.hu/userfiles/files/45614693147.pdfIn PDF document text
    • http://27derajat.com/assets/ckfinder/core/connector/php/uploads/files/17502941107.pdfIn PDF document text
    • http://allgeology.ru/ckfinder/userfiles/files/xuriwagireril.pdfIn PDF document text
    • http://agrobud.net/uploaded/file/pezexagomebopedutuzav.pdfIn PDF document text
    • http://auxerretv.com/content/public/file/73019295168.pdfIn PDF document text
    • https://art-gallery.mn/uploads/files/visagukubafeputure.pdfIn PDF document text
    • http://technimexvn.com/images/ckeditor/files/xunumorufaviv.pdfIn PDF document text
    • https://keyword-lda.pt/site/upload/file/purojagevejulopo.pdfIn PDF document text
    • https://harmony-lazienka.pl/Upload/file/sepesosevunosugimibuge.pdfIn PDF document text
    • http://fermobkorea.com/userfiles/file/20210910102658.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/558061e204ae69f504ed5dc590e5a912/wagemakajureviki.pdfIn PDF document text
    • http://suriyedostlukdernegi.org/image/files/55840463142.pdfIn PDF document text
    • http://www.cenlaenvironmental.com/siteuploads/editorimg/file/51914325830.pdfIn PDF document text
    • http://goraku-sangyo.com/userfiles/file/nixusojig.pdfIn PDF document text
    • http://gomsuhoangminh.com/app/webroot/uploads/files/31188665842.pdfIn PDF document text
    • http://sungwoo-n.com/userfiles/file/38621125902.pdfIn PDF document text
    • http://daiwavn.com/uploads/image/files/zemipubowok.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/tizom.pdfIn PDF document text
    • http://panziofabian.hu/fck_kepek/sozamifagova.pdfIn PDF document text
    • http://zhongjiukeji.com/upload_fck/file/2021-9-1/20210901115404627152.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-9-6/20210906235954226108.pdfIn PDF document text
    • http://architettogherardi.eu/userfiles/files/36159139250.pdfIn PDF document text
    • https://rdw-wolf.de/backend/ckfinder/userfiles/files/88940705934.pdfIn PDF document text
    • http://alnadaoil.com/userfiles/file/1525973274.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=screen+mirroring+option+in+mi+phonePDF 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_off0000d504.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD504 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED1B 10520 bytes
SHA-256: aa95cd66ad7d3c737e340a8aaf4e68bb22cde84989b9abdffd4e5d88af603956
font_02_sfnt_off000104cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104CF 18412 bytes
SHA-256: 1be97bb8e01ad6555eb3a442ccc220b5e6a762e0041e74bd8ec48d82fc497d4e