Malicious PDF — malware analysis report

Static analysis result for SHA-256 e168d503395fceb0…

MALICIOUS

PDF

87.7 KB Created: 2021-09-16 04:02:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 6b4808dc6d3af730709226c39150ef02 SHA-1: 3ecd06790f996aa6f5bd07bf766ca44945a7ce85 SHA-256: e168d503395fceb0e43893ab8e06658708cd0a792a413febd17b866ea56d4cce
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised websites and disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a link farm strategy, likely for SEO manipulation or to distribute malicious content. The ML classifier strongly flagged this PDF as malicious, suggesting it's part of a larger malicious operation, possibly initial access via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://smidgel.ru/uplcv?utm_term=iphone+11+max+pro+price+in+bangladesh+2020 PDF link annotation
    • http://jshanwoo.com/ckfinder/userfiles/files/gowelebesilivedexuxi.pdfIn PDF document text
    • https://dispecom.com/cms_dispecom/sgi_userfiles/userfiles/files/93647613081.pdfIn PDF document text
    • https://rajaketiga.com/contents/files/75670839121.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/07ebf730c6b074cfe96e5261ab06a569/mizulamumerasopafixiw.pdfIn PDF document text
    • http://www.kyousei-fukushi.or.jp/system/ckfinder/userfiles/files/kabatozi.pdfIn PDF document text
    • https://medosojewellery.com/userfiles/files/poxumaluzaka.pdfIn PDF document text
    • http://naosgym.com/userfiles/files/panesetu.pdfIn PDF document text
    • https://binarbaidtrading.com/public_html/userfiles/file/61914166238.pdfIn PDF document text
    • http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/1613f4413bd885---81684032947.pdfIn PDF document text
    • http://bharatdarshan.net/rgroup/ckfinder/userfiles/files/winaxar.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612fd9fde0e1a---90797650159.pdfIn PDF document text
    • http://abwferrellpkwy.com/uploads/files/61089091076.pdfIn PDF document text
    • https://olterus.net/contents/files/maxan.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/16130585106d50---51797997597.pdfIn PDF document text
    • http://bishnutoursandtravels.in/userfiles/file/koraguwarufotamo.pdfIn PDF document text
    • https://branchennachweis.eu/userfiles/file/rizug.pdfIn PDF document text
    • http://coinproject.com/userfiles/image/file/nibazizuvewolij.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c4b8d0a23b---pirotajoti.pdfIn PDF document text
    • http://15441707.com/data/board/file/20210903211651.pdfIn PDF document text
    • https://dodomacnosti.net/data/file/fofelagudesuw.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/161355efb848c2---wogulovuzefigaduwixera.pdfIn PDF document text
    • http://vouchertiket.com/airplane/ckeditor/uploads/files/158859168.pdfIn PDF document text
    • http://etkenkalip.com/files/54830149015.pdfIn PDF document text
    • http://mimarkamilozkartal.com/userfiles/files/72620934300.pdfIn PDF document text
    • https://rockyhotelsgroup.com/uploaded/files/10596179806.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/161428c11e3563---57766165436.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_off0000eb3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB3F 11352 bytes
SHA-256: 35cf5ba4d5847e7205e8ad417c550af4c8e02125e61b5bdb12c13064747d7f1e
font_01_sfnt_off0001055c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1055C 19204 bytes
SHA-256: cef19ba125efb6c18300fd2ae274251410bc2a477a672f27df270fe0d9f8c5dc
font_02_sfnt_off00013864.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13864 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1