Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd5fcc4bec936761…

MALICIOUS

PDF

75.4 KB Created: 2021-09-08 23:26:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c71280efd4dcfb0fe47d3ebeae3356d5 SHA-1: df9f3604363ccbc3d2efc52140b0a852230b0731 SHA-256: fd5fcc4bec93676121f47bdf2a107c3a815bdb99dbec204ba48ec9a65a396103
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 distinct external URIs, many pointing to disposable hosting, strongly suggests a link farm designed to redirect users to potentially malicious sites. While no scripts were explicitly extracted, the PDF structure and the nature of the URLs point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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 http://buyo-g.net/userfiles/file/kideramenipipeti.pdf In PDF document text
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/ea6b35abfef826ef749baa4b04fa2eec/sozobazegirofutanuda.pdfIn PDF document text
    • https://resortweeks.pro/userfiles/file/duwozafawiruduxa.pdfIn PDF document text
    • http://njchemland.com/upload/files/guvowubavez.pdfIn PDF document text
    • http://namadagaskare.ru/ckfinder/userfiles/files/63807812621.pdfIn PDF document text
    • http://kezmosas.hu/files/file/valowijun.pdfIn PDF document text
    • http://hodoan.net/userfiles/file/bivaruluvesixeg.pdfIn PDF document text
    • https://eghamatsafar.ir/basefile/eghamatsafar/files/vujive.pdfIn PDF document text
    • https://wecareprogram.org/images/file/77120807530.pdfIn PDF document text
    • https://zniczekowalczyk.com/user_images/file/veluzovevijini.pdfIn PDF document text
    • http://satisfytech.com/ck/upload/files/vizowega.pdfIn PDF document text
    • http://iamsong.vn/uploads/files/pariso.pdfIn PDF document text
    • https://u15.ch/ckfinder/userfiles/files/vakijobonemenawasofu.pdfIn PDF document text
    • https://bibliotheque.ville.deux-montagnes.qc.ca/ckfinder/userfiles/files/bawijo.pdfIn PDF document text
    • http://allivecoat.com/userData/board/file/xenekoju.pdfIn PDF document text
    • http://asude.istanbul/ck_images/files/fimemapilo.pdfIn PDF document text
    • http://thepokewave.com/uploads/files/81839015199.pdfIn PDF document text
    • http://opuspoint.com/ckfinder/userfiles/files/vojilixenilekolebuxeja.pdfIn PDF document text
    • https://itscebu.com/upload/file/20210907090214.pdfIn PDF document text
    • http://nguyenphat.com/public/default/ckeditor/files/pazuxirezigoxi.pdfIn PDF document text
    • https://smobiil.eu/userfiles/files/30635995418.pdfIn PDF document text
    • http://neodev.space/wp-content/plugins/formcraft/file-upload/server/content/files/1613748e59f767---sigenidebir.pdfIn PDF document text
    • http://railwaysrailroads.com/upload_files/files/lixopuluzepemifiv.pdfIn PDF document text
    • http://hykylalumni.org/userfiles/34752989057.pdfIn PDF document text
    • https://bloomlight.pl/_bloom/file/gisifavimefuwukug.pdfIn PDF document text
    • http://robalton.es/Albums/images/file///rupapidutalap.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=forgot+pin+for+androidPDF 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_off0000c67b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC67B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000de92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE92 10304 bytes
SHA-256: 1b68a2cdbd87078fd8e2573d5591491399cc5d58320ece62290bb0fc0189317c
font_02_sfnt_off0000f5a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5A5 16588 bytes
SHA-256: 6c6afb51f8b2c5ec507f018f26f25918ba8b30ef65c918892b8e628e684ffc82