Malicious PDF — malware analysis report

Static analysis result for SHA-256 b635813c24a55147…

MALICIOUS

PDF

73.0 KB Created: 2021-06-26 04:10:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: cc128440edc6a38c2f50b4840af6a9ba SHA-1: 4f6f614c09a5257058415690e82463faf56593e8 SHA-256: b635813c24a55147e40268ba7845a6efc2f53f98b15d6ddb0383aace46c28c27
156 Risk Score

Malware Insights

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

This PDF file was flagged by ML classifiers and ClamAV as malicious. It contains a link farm pointing to multiple domains, many of which are hosted on compromised WordPress sites or disposable domains, suggesting an attempt to distribute malicious content or conduct phishing. The presence of numerous PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://amadpich.com/userfiles/file/45284740294.pdf In PDF document text
    • https://barcelonamedicalcenter.com/files/galeria/files/gorozirazijibagofipojew.pdfIn PDF document text
    • http://apsons.eu/files/file/kojuti.pdfIn PDF document text
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba38ada2860---gumamo.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/b8ad41484b79d5a979d4b2dacfd4d47e/penoxumebidoketuv.pdfIn PDF document text
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d29a5c785c---73567462061.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/94870417603.pdfIn PDF document text
    • https://plasy.com/uploads/file/61164609484.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f047340c7f---vuwedabosemiragisu.pdfIn PDF document text
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/pcb8gml68rlr4gl7i2co0n68eh/wuwirozeziposuvefolaxoja.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/c7f82a838d16897f7824120d5a224b60/jadenadakumopu.pdfIn PDF document text
    • http://www.anclupnapoli.it/userfiles/file/tagafubigidum.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160ae5ad7b11eb---64376158832.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608903fe692f3---85694458665.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/4fe82c3b16b56531839b2b07d9827c65/pawabedikowew.pdfIn PDF document text
    • http://esejsc.com/upload/files/fumujojugeniv.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/mugm8hun76jenjjiepfjkqql82/pabadobapep.pdfIn PDF document text
    • https://lederstuehle-shop.de/ckfinder/userfiles/files/10247814180.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160b2e91f770cf---31645335688.pdfIn PDF document text
    • http://xn--82cac8d3ajrc0gd0bo4a7nf3qg.com/userfiles/files/mubapawetoxixoxutojum.pdfIn PDF document text
    • https://mygamedaysports.com/wp-content/plugins/super-forms/uploads/php/files/4a42a7ffb7c6a2b813e66bd02db5c6f0/91425804701.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c751759e7d6---guxot.pdfIn PDF document text
    • http://www.thunderesp.com/ckfinder/ckfinder.htmlfiles/fobev.pdfIn PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084f70adab92---sebuletewip.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=the+dream+song+from+sharkboy+and+lavagirl+lyricsPDF 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_off0000bc97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC97 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d4a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4A9 15536 bytes
SHA-256: cca88e696fd2007a52dbf4fb9e8ac350dbb6f56ae374e60a4e22122a2adb435c
font_02_sfnt_off0000fcc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCC0 11200 bytes
SHA-256: d696b06d34fc5edfc0428f76dd1ecdb323ca1c809cb0936444172561409194b5