Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6667cc806661ac7…

MALICIOUS

PDF

84.9 KB Created: 2021-09-21 02:09:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: fa87c39b7229e42f697fc7d8d4691fa3 SHA-1: c91108469d524d39d056547e0d2d9108507248ba SHA-256: b6667cc806661ac70415455f7170ed132c6f2e7f5c733e93c5708606e72c7cb7
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV, indicating malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests it functions as a link farm, directing users to numerous distinct domains. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the link farm heuristic point towards an attempt to redirect users to potentially malicious sites, possibly for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://com123.vn/uploads/file/nawofowote.pdf In PDF document text
    • http://pribatu.lamilagrosaimport.com/images/files/jadunidado.pdfIn PDF document text
    • https://emenu.hu/editor_up/88238082859.pdfIn PDF document text
    • https://www.wappa.com.au/siteadmin/ckfinder/userfiles/files/jikojijuzizapagakanalu.pdfIn PDF document text
    • http://daglichtfilters.nl/ckfinder/userfiles/files/54270163956.pdfIn PDF document text
    • http://gruppocaminiti.it/userfiles/files/tageviweribag.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/afd247b6ac5d0e5919782981e40023de/tagudomenajanex.pdfIn PDF document text
    • http://xn--939a66v0zjo3bcvdmrp.com/data/ckfinder/files/55752049994.pdfIn PDF document text
    • https://trungtammatnamviet.vn/upload/files/dolufalunami.pdfIn PDF document text
    • http://cec-intl.ru/app/webroot/files/file/26419227944.pdfIn PDF document text
    • http://hichipper.com/hichipper/uploadfile/file/2021090117113973499.pdfIn PDF document text
    • http://solarwindependence.com/ckfinder/userfiles/files/julabogujilo.pdfIn PDF document text
    • http://pmke.cz/pictures/files/tejunerowirabuwunuti.pdfIn PDF document text
    • https://subarini.ro/mm/file/97638164657.pdfIn PDF document text
    • http://cs-web-design.de/ablage/userfiles/files/87603653390.pdfIn PDF document text
    • https://belitour.ir/basefile/belitourir/files/64890839666.pdfIn PDF document text
    • https://htchninc.com/d/files/90579775803.pdfIn PDF document text
    • https://loppisidjupdalen.se/images/uploaded/file/bonojujuj.pdfIn PDF document text
    • http://aguito.madteam.net/ckfinder/userfiles/files/88213747815.pdfIn PDF document text
    • https://tahuacoop.com/cms_gpadmin2015/sgi_userfiles/userfiles/files/82214527873.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/tog2dvng4rufj37gf3re5v12u3/26959428043.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=samsung+galaxy+s2+plus+lollipop+romPDF 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_off0000e6aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6AA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fec1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEC1 10876 bytes
SHA-256: db686a539fc417d3180a1f0878586f8be6cb73d47162fb735966d79e70467687
font_02_sfnt_off000117d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117D5 17792 bytes
SHA-256: 3afce1756c0cad61c7f96dea38c635c85c2287edafe74640640213c888f8893c