Malicious PDF — malware analysis report

Static analysis result for SHA-256 11dc72231f55e544…

MALICIOUS

PDF

73.5 KB Created: 2021-09-14 01:44:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b96886c0c036fd7525f788ccad9e8ec1 SHA-1: 620c6e1935f567647704be21c05895c9b50e3e66 SHA-256: 11dc72231f55e5448905ccc6f1c8f7bb681e48ba4986a92e099fccf2902f9f26
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains embedded JavaScript and numerous external URIs, many pointing to potentially malicious domains. The PDF structure suggests it acts as a link farm, directing users to various external sites, which is a common tactic for phishing or distributing further malware. The presence of embedded JavaScript indicates an attempt to execute code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 6

  • 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.
  • 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://atut-biuro.com/uploaded/file/9890733279.pdf In PDF document text
    • https://johanbjerke.se/userfiles/file/jexapubufogisu.pdfIn PDF document text
    • http://www.smartlandgroup.com/ckfinder/userfiles/files/93491949418.pdfIn PDF document text
    • http://www.cerel.eu/images/wyswig_images/file/sedexiso.pdfIn PDF document text
    • https://bnbtravels.com/ckfinder/userfiles/files/mimurunoralumufu.pdfIn PDF document text
    • http://m-styleauto.com/js/upload/files/60795201137.pdfIn PDF document text
    • http://lscapital.it/images/file/napugub.pdfIn PDF document text
    • http://futuralagoparking.eu/userfiles/files/32342886828.pdfIn PDF document text
    • https://sbsoftware.ro/admin/userfiles/file/wofujevitudavuzis.pdfIn PDF document text
    • http://asupuro.com/upload/save_image/files/numuwepopireboguwijoxu.pdfIn PDF document text
    • http://narcisse.sk/editor_uploads/files/94599562378.pdfIn PDF document text
    • http://duetsepolno.pl/userfiles/file/66320333256.pdfIn PDF document text
    • http://vektorma.ru/uploads/assets/file/45884164403.pdfIn PDF document text
    • http://a-pro-peau.fr/userfiles/file/fibodorekutasibu.pdfIn PDF document text
    • https://vinasimex.com/uploads/file/bezama.pdfIn PDF document text
    • http://primaria-ciocirlia.ro/media/file/97385403845.pdfIn PDF document text
    • https://cakenflowersonline.com/userfiles/file/14454997311.pdfIn PDF document text
    • https://cmottaviproductive.it/uploads/file/71680297861.pdfIn PDF document text
    • https://www.carnesvarejo.com.br/assets/ckfinder/core/connector/php/uploads/files/658058093.pdfIn PDF document text
    • http://sysquare.com/UserFiles/files/51356377225.pdfIn PDF document text
    • https://globalathena.com/ckfinder/userfiles/files/gabedilaluxedebafavu.pdfIn PDF document text
    • http://taxfreepoint.com/file/fumarakabej.pdfIn PDF document text
    • https://sealskinz.ru/files/file/14194357188.pdfIn PDF document text
    • http://safarekhoob.ir/basefile/safarekhoobir/files/lifot.pdfIn PDF document text
    • https://kuzeyilac.com/resimler/files/wokuwigejavufokaw.pdfIn PDF document text
    • http://sung1.com/upload/files/99819852475.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=apk+ninja+warriorPDF 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_off0000bdb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDB5 17264 bytes
SHA-256: 7b7f8e154ad8b5d9dd89bf31699afe0abd043f48fd074c066c5b743361ec2aa5
font_01_sfnt_off0000ea27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA27 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001023e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1023E 10092 bytes
SHA-256: d10ca94f6da2ebb10ef8ee3942a3df3a188c99cf8ae19fc4df9f827ffc215d1c