Malicious PDF — malware analysis report

Static analysis result for SHA-256 073fd42c1e7fb312…

MALICIOUS

PDF

80.8 KB Created: 2021-09-08 20:32:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: d392fb8e2dd5d7ebf403b27e83d65a14 SHA-1: 0e732eed76c2dde147a0bc56021dd870bb62a6f2 SHA-256: 073fd42c1e7fb3120a6ed9f2f368498ce546ce75be37960f041e73e278e0ea86
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for exploiting vulnerabilities or redirecting users to malicious sites. Multiple heuristics indicate the PDF is part of a link farm, with many URLs pointing to potentially compromised or disposable hosting. The ML classifier strongly flagged this PDF as malicious, supporting the conclusion that it is designed for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • 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.
  • 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://huntic.ru/uplcv?utm_term=citrus+greening+symptoms+pdf PDF link annotation
    • http://dungcubepgiangtrinh.com/webroot/img/files/duvavulefokeg.pdfIn PDF document text
    • http://k-ookuma.com/js/upload/files/zexulim.pdfIn PDF document text
    • http://bmfjhjk.friend-match.com/upload/files/kalijefamunelefe.pdfIn PDF document text
    • http://www.museopizarra.com/ckfinder/userfiles/files/63463646177.pdfIn PDF document text
    • http://irk-yoga.ru/upload/files/ditiparikitakagakozute.pdfIn PDF document text
    • http://tjsyjdq.com/v15/Upload/file/2021932212358199.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/161367694b3d58---buzubazadepazak.pdfIn PDF document text
    • http://tiendanatacion.com/noticias/files/33718670752.pdfIn PDF document text
    • http://honderhotel.com/UploadFiles/FCKeditor/20210908114609.pdfIn PDF document text
    • http://internet-trade.eu/UserFiles/file/mijazu.pdfIn PDF document text
    • http://ytbozhuo.com/upload/file/030532317554.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/1bde4f595469c4677911064f91c52501/27853767627.pdfIn PDF document text
    • http://ainut.fi/userfiles/file/xowisofokerufuno.pdfIn PDF document text
    • http://hadt.vn/upload/files/14190453158.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/2549a76a1693edd837f0d94a4075861f/70957878026.pdfIn PDF document text
    • http://cokhihoangvinh.com/uploads/userfiles/file/gabesiwokatokezezoj.pdfIn PDF document text
    • http://princeverma.in/uploads/files/zipinerofigow.pdfIn PDF document text
    • https://internationalmedia.com/userfiles/file/40377701191.pdfIn PDF document text
    • http://nenorm.com/files/files/57161788038.pdfIn PDF document text
    • http://galerie45.com/userfiles/file/zagugikoxugajuzu.pdfIn PDF document text
    • http://medtravel.lv/images/hand_uploaded/files/10346645250.pdfIn PDF document text
    • http://dobre-jaja.com/Upload/file/47551042347.pdfIn PDF document text
    • http://myrbacken.se/login/ckfinder/userfiles/files/toxerakenep.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_off0000d59b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD59B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000edb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB2 10876 bytes
SHA-256: f3341cf5b5861cb84b8b0aad987b745b778d03572e0472f17ddea28a151faef4
font_02_sfnt_off000106a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106A8 18016 bytes
SHA-256: 8616751341c5ad96a8ba96ae90cb6573f87211a91c70afd2f15dbbb088e8c0d2