Malicious PDF — malware analysis report

Static analysis result for SHA-256 f994c6612ce51c96…

MALICIOUS

PDF

86.2 KB Created: 2021-08-07 09:35:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 38d207a61ac3575b1a8ad2d5612968f6 SHA-1: 29f226aa7aa116babe2145f874d0676258f9d98b SHA-256: f994c6612ce51c96624d503cbc02a70226747e2f36f0176c0ab7634e78609ba9
96 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm or phishing lure. The ML classifier strongly indicates maliciousness. The document body is heavily obfuscated, preventing a clear understanding of its specific content, but the overall structure and URL analysis point towards an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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://smilepaper.tw/archive/upload/files/zudotumerofisupilixok.pdf In PDF document text
    • http://teenmag.cz/userfiles/file/81969614130.pdfIn PDF document text
    • https://girilawfirm.com/content_files/files/13306025964.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/5a6c62b4abaa74bbcc06ce19699bd23b/wavenikufusabawezowelam.pdfIn PDF document text
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/fs63ih72gst3d58bud88t59p33/tozazimimurukufunoxo.pdfIn PDF document text
    • http://vieclamtaichinh68.com/upload/files/jikosojudabiwu.pdfIn PDF document text
    • https://gute-reise.ru/i/files/files/mogikilajazifogaguboki.pdfIn PDF document text
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/fd488e7eea2bed916f62f81553eb68fd/51164228472.pdfIn PDF document text
    • http://wumag.pl/userfiles/file/49874960895.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/751812affe9b77dedd936466edcfcec2/kubaja.pdfIn PDF document text
    • https://sanxuattrucauthangkinh.com/Images_upload/files/21594845741.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160dae5610dab5---fetuxifurekukibasegokezot.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607626a312734---rufonazuwevorasasel.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160ab3a0cb0d23---197715836.pdfIn PDF document text
    • http://shethof.ch/cgi-bin/dynamisch/file/ziwifusigomafo.pdfIn PDF document text
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/124aa2419111a5b718d1d917f4426d50/17965160670.pdfIn PDF document text
    • http://sireny.net/share/files/57907507641.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160ba5ae73b6b7---75919472634.pdfIn PDF document text
    • https://yziact.fr/wp-content/plugins/super-forms/uploads/php/files/314tpko9te78h8ss6t00li09bc/85478548314.pdfIn PDF document text
    • https://livingcircles.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb73ef30cd---90947881913.pdfIn PDF document text
    • https://kawanmto.net/contents//files/52144540645.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=what+does+a+citizens+bank+cashier%27s+check+look+likePDF 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_off0000efea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFEA 10784 bytes
SHA-256: f046f1d1fc4e16056d1d953f49fcbad8a6bb0edf4a2d97ffd46a81f344a84d8a
font_01_sfnt_off000108cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108CC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000120de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120DE 15968 bytes
SHA-256: 6187c1ef03dccf1ff6cce5cf7f0e8253564910320bfbf629dd1af01d367d4138