Malicious PDF — malware analysis report

Static analysis result for SHA-256 0165628401008dea…

MALICIOUS

PDF

79.2 KB Created: 2021-09-15 16:49:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 394a52dda5a895015808b4cb0351ca39 SHA-1: 3af3fe1a52a383ab047d346f8485c7a901997274 SHA-256: 0165628401008dea4d19af63df374d4c8ecb265fa2efbd7f89fb1f36831dc777
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains embedded JavaScript and a large number of external URIs, many hosted on disposable domains, consistent with a phishing or link-farming attack. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically points to a link farm strategy on disposable hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://cructi.ru/uplcv?utm_term=change+themes+on+android PDF link annotation
    • https://ikincielinmak.com/upload/ckfinder/files/fuvoxirukugowasax.pdfIn PDF document text
    • http://constantcontinuity.com/membership/data/files/38351572653.pdfIn PDF document text
    • https://santchavarabed.in/ckfinder/userfiles/files/ramezuvubine.pdfIn PDF document text
    • http://art-wonders.com/ckeditor/ckfinder/core/connector/php/uploads/files/xobeberitofudaxidonosu.pdfIn PDF document text
    • https://27061010.com/uploads/files/202109021930132896.pdfIn PDF document text
    • http://lica.plovdivweek.com/js/ckfinder/userfiles/files/muxejazotupatunix.pdfIn PDF document text
    • http://aalzkj.love-mrt.com/upload/files/zotexijojogoraboguvaribu.pdfIn PDF document text
    • https://akgoz.zemta.com/uploads/files/voforuj.pdfIn PDF document text
    • http://tehpromyar.ru/media/file/62191525514.pdfIn PDF document text
    • http://casaperferiesantamariagoretti.com/writable/public/userfiles/file/regotazelazoxekixevabole.pdfIn PDF document text
    • https://www.barrau-philippe-sedeco.fr/ckfinder/userfiles/files/finaxujevoxo.pdfIn PDF document text
    • https://xeroxexpres.cz/userfiles/file/98024324645.pdfIn PDF document text
    • http://topp.pl/_topp/file/suwamozopuzukiwamupo.pdfIn PDF document text
    • https://tourpon.kr/FileData/ckfinder/files/20210905_7635F93DD8D12743.pdfIn PDF document text
    • https://www.kuwaitpolyurethane.com/ckfinder/userfiles/files/81021131283.pdfIn PDF document text
    • http://www.horakgolf.cz/ckfinder/userfiles/files/fanudosibivometujipaxi.pdfIn PDF document text
    • https://sunsetlearningcenter.com/userfiles/file/mojesesik.pdfIn PDF document text
    • http://getdol.com/page_data/file/figixeno.pdfIn PDF document text
    • http://pravkniga.ru/files/userfiles/files/kiruvi.pdfIn PDF document text
    • https://nicklason.se/ckfinder/userfiles/files/xoditax.pdfIn PDF document text
    • http://www.valathors.com/ckfinder/userfiles/files/roturitepasovaz.pdfIn PDF document text
    • http://mictrogiang.com/userfiles/files/23254542950.pdfIn PDF document text
    • http://sjanzee.nl/file/pofufewotuzosoxopegemeref.pdfIn PDF document text
    • https://digireg.se/upload/49797951689.pdfIn PDF document text
    • https://marmetal.cevhertemizlik.com/userfiles/files/82409640865.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_off0000d094.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD094 10680 bytes
SHA-256: 6a8972d50982f3677f0e5e82573b4f30c61520c0eda5b48d080d81dcd1504714
font_01_sfnt_off0000e8af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8AF 17900 bytes
SHA-256: 2a456ba85c32e2014a45a0b3183914b125da40c979bc06ff1d5bbb751676b4b6
font_02_sfnt_off000116e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1