Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4e088fe1016310b…

MALICIOUS

PDF

74.8 KB Created: 2021-09-14 13:04:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f94056d33a122f062f1a84f0514bb32b SHA-1: 4429f8d89fe6c6a91745ab0f3fe7d7d075198a6f SHA-256: c4e088fe1016310bbeb08c10fe097fd9a57c7ef6ebe98647cbdaaf4cda0d302b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristic firings, particularly PDF_SEO_DISPOSABLE_LINK_FARM and PDF_URI, reveal that the document contains numerous embedded links pointing to potentially malicious domains. These links are likely used to redirect users to phishing sites or download further malware, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://catamma.ru/uplcv?utm_term=sdk+android+para+windows+7 PDF link annotation
    • https://smartmedia.ro/app/webroot/files/userfiles/files/97828590299.pdfIn PDF document text
    • http://yournamebadges.com/withyourdog/cms_uploads/file/16226677864.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/87ccba63083772f0bab79af02e0ea150/kadozebavubenanejovanirur.pdfIn PDF document text
    • https://myparrotfood.com/user_files/files/mowetij.pdfIn PDF document text
    • http://hoangminhphatkorea.com/webroot/img/files/defoj.pdfIn PDF document text
    • http://brenno-tojestto.pl/userfiles/file/16054163031.pdfIn PDF document text
    • http://dijladentalcenter-qa.com/userfiles/file/5833072004.pdfIn PDF document text
    • http://seoulmenu.com/uploads/files/mijelozebojugapu.pdfIn PDF document text
    • http://wakesup.org/userfiles/file/1100122269.pdfIn PDF document text
    • https://fablab808.com/nbloom/fckuploads/file/dudakoko.pdfIn PDF document text
    • http://kleinschadenexpert.com/userfiles/file/texuw.pdfIn PDF document text
    • https://synersys.fr/contenu/file/notubagisanap.pdfIn PDF document text
    • http://khyljg.com/uploadfiles/files/77269638771.pdfIn PDF document text
    • https://nyirfa.hu/uploads/files/sozana.pdfIn PDF document text
    • http://oreade-breche.fr/userfiles/file/tizofitaluvareveniterir.pdfIn PDF document text
    • http://xn--b1adcbbai1bezln.xn--p1ai/content/File/65337167599.pdfIn PDF document text
    • http://psystems.gr/Administrator/uploads/userpics/OutPostImages/files/penixozesixogok.pdfIn PDF document text
    • http://www.pibmg.com.br/ckfinder/userfiles/files/files/xorawibepegodu.pdfIn PDF document text
    • http://www.florentmaussion.net/userfiles/File/35460947655.pdfIn PDF document text
    • http://ukicda.com/admin/fckeditor_upfiles/file/2021091400575380554.pdfIn PDF document text
    • http://zuche0551.com/upload/file/bapurebojub.pdfIn PDF document text
    • https://htchninc.com/d/files/pijufalifafi.pdfIn PDF document text
    • http://checopharma.com/upload/files/90006483115.pdfIn PDF document text
    • 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_off0000c2ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2EF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000db01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB01 16568 bytes
SHA-256: dab76e5ea60af97e6f97f532aa204abaebc3a9d496aa51babd7c26574ac3c96b
font_02_sfnt_off000105bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105BF 10412 bytes
SHA-256: d1e95bce18712dc3f9dda2d3cb6475307b57b47567e9252a3a5be704ea912225