Malicious PDF — malware analysis report

Static analysis result for SHA-256 ee6a3f8d0220b7ca…

MALICIOUS

PDF

72.3 KB Created: 2021-09-19 01:24:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4e01d46bb9d7cf92d257206b8b1c621e SHA-1: 22e47fff0fbadeb3bf6ddd9214d535f075e8c7cd SHA-256: ee6a3f8d0220b7ca0165e4b9e34a7841afcf4544a69d5433e06b9161558a7ccc
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF file detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and multiple links to external URLs, some of which are algorithmically generated and hosted on disposable domains, indicating a phishing or malware distribution attempt. The presence of embedded JavaScript suggests an attempt to execute code within the PDF viewer, likely to download a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://buyyoutubesubscribers.com/ci/userfiles/files/zetub.pdf In PDF document text
    • https://osakaav.com/userfiles/files/56882884174.pdfIn PDF document text
    • http://kibunajcc.com/ckfinder/userfiles/files/tukazenaxunemuvozeg.pdfIn PDF document text
    • http://minhledtran.com/luutru/files/27279457433.pdfIn PDF document text
    • http://papianiarch.it/userfiles/files/16404436096.pdfIn PDF document text
    • http://studioboscono.it/userfiles/files/40129885634.pdfIn PDF document text
    • http://shangrilatheshow.com/ckfinder/userfiles/files/57027025101.pdfIn PDF document text
    • http://jfhcoaching.nl/userfiles/files/17815278615.pdfIn PDF document text
    • http://kingtonkatsu.com/uploads/files/sedorejizunafejojobefa.pdfIn PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c5ce857ada---3021317533.pdfIn PDF document text
    • http://opt-russtd.ru/data_center/upload_pictures/file/nasudimurujikutu.pdfIn PDF document text
    • http://fabriquetextil.com/js/new/fckeditor/userfiles/file/wifufinuzofat.pdfIn PDF document text
    • http://devitohomesorlando.com/userfiles/files/nufiwabamorom.pdfIn PDF document text
    • https://dagvandearchitectuur.be/_files/file/52455309957.pdfIn PDF document text
    • http://thepnguyentran.vn/media/ftp/file/vafakepuwarawafol.pdfIn PDF document text
    • https://shastriratanchatterjee.com/ckfinder/userfiles/files/73602286169.pdfIn PDF document text
    • http://jhdljz.com/userfiles/file/1630951662.pdfIn PDF document text
    • http://kayapaliinsaat.net/file/79391309818.pdfIn PDF document text
    • http://arabic.cz/ckfinder/userfiles/files/35490053520.pdfIn PDF document text
    • https://superiorservicesandsolutionsfl.com/nbloom/fckuploads/file/90572998095.pdfIn PDF document text
    • https://angelsstaff.com/uploads/file/tunoremivagedapit.pdfIn PDF document text
    • https://discovercefalu.com/_data/images/file/42748874503.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+cast+my+phone+to+laptopPDF 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_off0000b59d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB59D 10640 bytes
SHA-256: 874a4764fd4e493f414c8db4e6f41bc45daa372e0c1cb9692864a76f18543323
font_01_sfnt_off0000cdde.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDDE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e5f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5F0 17624 bytes
SHA-256: 3e49960463e49b57356b3d6009f2bd33b8e9901ae9e46a534ce9fd7212ce8535