Malicious PDF — malware analysis report

Static analysis result for SHA-256 29758169c42eea07…

MALICIOUS

PDF

86.7 KB Created: 2021-10-05 10:23:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: da3ef214556f7d2e1546a91b17902533 SHA-1: ae55ea56196d03e05e2f0a9a3b3f774bb255d815 SHA-256: 29758169c42eea072ab77829ca13d537b4fd75d08bea8146d55a740ea5f311c4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is identified as malicious by ClamAV and an ML classifier. Heuristics indicate it functions as a link farm, with numerous URLs pointing to potentially compromised WordPress sites or disposable hosting. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather to host links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://medvor.ru/uplcv?utm_term=biggest+coconut+producer PDF link annotation
    • https://textosolutionslinguistiques.ca/upload/editor/file/87498810602.pdfIn PDF document text
    • http://nepaltravelsandtrekking.com/userfiles/file/83921076559.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/ffb9b533072a0099c4003073c8b2239b/15256078208.pdfIn PDF document text
    • http://mbjarrahi.com/UploadedFiles/New/file/boveropawe.pdfIn PDF document text
    • https://anzhero-sudzhensk.verlauf-ekb.ru/admin/ckfinder/userfiles/files/25479990899.pdfIn PDF document text
    • http://xn--72c7caerxx0d3a9eve.com/UserFiles/File/mivedasekezud.pdfIn PDF document text
    • http://zamgph.com/uploads/file/261459599658.pdfIn PDF document text
    • http://trumoi-khutrung.com/upload/files/lewaxolixatal.pdfIn PDF document text
    • http://skyrybupaslaugos.lt/uploads/files/naxipa.pdfIn PDF document text
    • https://gulfsupremesa.com/ckfinder/userfiles/files/dikibagubinovidimiwefexer.pdfIn PDF document text
    • http://baovethanglongmb.com/upload/files/84883339239.pdfIn PDF document text
    • http://kargiskola.ge/myadmin/ckeditor/ckfinder/userfiles/files/90867534354.pdfIn PDF document text
    • http://www.cafeinca.com/img/public/contenido/file/gafumifikoxojuku.pdfIn PDF document text
    • http://piemonteforyou.it/userfiles/file/gawitufo.pdfIn PDF document text
    • http://musicfriend.vn/public/default/ckeditor/files/78345220197.pdfIn PDF document text
    • http://byty-pardubice.eu/UserFiles/File/denezividaxofobugot.pdfIn PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/9lqoqdrd0g54hldl8gpfpe3ut6/jomelegoganefame.pdfIn PDF document text
    • http://nbc.com.vn/ckfinder/userfiles/files/23735551643.pdfIn PDF document text
    • https://oasis-travel.ro/files/pujaz.pdfIn PDF document text
    • https://rusepress.com/uploads/wysiwyg/files/55963284207.pdfIn PDF document text
    • http://bugaboo-buffalo.eu/UserFiles/File/76799832298.pdfIn PDF document text
    • http://mvpbuilding.com/userfiles/file/zogivijozufoz.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/lg9pol90j3jusvr0ct8m0n51e1/wudovomarutovokeji.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_off0000e544.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE544 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD5B 10632 bytes
SHA-256: f40a70805bd5e6b7c1d9b8e433de808ac460e6d06226d1a19bb484abbec4a964
font_02_sfnt_off0001159f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1159F 21336 bytes
SHA-256: e420180e816aee127e8b33de148876b447e03e464ccfad20ee0be3bd5e1d445e