Malicious PDF — malware analysis report

Static analysis result for SHA-256 42a044d1d0e9c41f…

MALICIOUS

PDF

75.6 KB Created: 2021-09-19 00:47:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6e13be5f9bf0dc9a14008aa7d802a1bb SHA-1: 3cb92e563e1b186862884fbaba9b0aa7263b7fbd SHA-256: 42a044d1d0e9c41f430a82fab24c9f8e768bad3f9c2a7c5c216356d7c8e26387
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many hosted on compromised or disposable domains, characteristic of a link farm used to distribute malicious content or phish for credentials. The ML classifier and ClamAV detection strongly indicate malicious intent, likely involving exploitation or redirection to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://laborke.ru/uplcv?utm_term=freezing+temp+of+water+in+fahrenheit PDF link annotation
    • http://gibisch.biz/files/files/52343099021.pdfIn PDF document text
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/86591d04787e32797682e3ff47bb7555/gimisudimowebiziduraze.pdfIn PDF document text
    • https://commonwealthsportsawards.com/userfiles/file/vizejiwowedak.pdfIn PDF document text
    • http://autoneza.cz/UserFiles/File/xasajudofibomijavat.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613886b9cf76b---21187886768.pdfIn PDF document text
    • http://generaltubi.com/container/ckfiles/files/vubipodajud.pdfIn PDF document text
    • https://keluargamimpi.com/contents/files/59848954814.pdfIn PDF document text
    • http://lapmaymn.samdigroup.vn/app/webroot/upload/files/vinawebuwiwesajobof.pdfIn PDF document text
    • http://safiorida.nl/operatori/userfiles/file/lanumutujirob.pdfIn PDF document text
    • https://lodoshosting.com/calisma2/files/uploads/19037871286.pdfIn PDF document text
    • http://www.naturhalles.fr/fckeditor/userfiles/file/kupibelat.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145cd443ae55---68999613019.pdfIn PDF document text
    • https://brincandoeaprendendo.com/fotosempresa/files/rajumopexibe.pdfIn PDF document text
    • http://qualityfirstservices.pro/testingsites/advantage_aviation/assets/media/file/nadekibadatarawunevoxux.pdfIn PDF document text
    • http://haai.org/upload/file/2462604995.pdfIn PDF document text
    • https://decoveinvestment.com/userfiles/file/pigokixufi.pdfIn PDF document text
    • http://ex2010.com/uploadfile/file/2021091610451973499.pdfIn PDF document text
    • http://twfindia.in/userfiles/files/94272086773.pdfIn PDF document text
    • https://inprovitcentroamerica.com/ckfinder/userfiles/files/29018175531.pdfIn PDF document text
    • http://bularz-auto.pl/images/userfiles/file/31271915470.pdfIn PDF document text
    • https://terminarz.online/kosmetyczka/krakow/files/19159601735.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_off0000c40f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC40F 10712 bytes
SHA-256: 73c1b870f1bee6e428a7b3035176b32a291d76104a3d065108b736fcf846ea18
font_01_sfnt_off0000dc87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC87 17184 bytes
SHA-256: 48dd527721010e27ae23e24c1efd003b1be0b91f306e743b5a1dec9038ed9c92
font_02_sfnt_off00010919.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10919 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1