Malicious PDF — malware analysis report

Static analysis result for SHA-256 635d8806e5adf689…

MALICIOUS

PDF

83.7 KB Created: 2021-06-25 12:41:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 7a9bbc2d775a5fc65a9a4623237f15e9 SHA-1: 0d251b0c158dbd2026c697376e693edce33d397f SHA-256: 635d8806e5adf689a0917604d3718ba5719b47a345a5100916326afee42e3e5d
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised websites, suggesting a phishing or malware distribution scheme. The PDF structure and link farm heuristics indicate it's designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://www.rkcomdesignservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b9e16b3661---golixi.pdf In PDF document text
    • http://ricarda-allegra.de/userfiles/file/72029124145.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607edb0a3413d---wejagubum.pdfIn PDF document text
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/5bcb5b587f6832ead8b5e9644e6011d0/95797345940.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160812713b0b1f---setumapurupafuwul.pdfIn PDF document text
    • https://boucherienabli.com/uploads/FCK_files/file/17068689321.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/79d456ad6eb9a5b79302ea7493785198/roteferuwosurafowi.pdfIn PDF document text
    • http://oasis-inwaste.asia/files/file/86829033864.pdfIn PDF document text
    • http://stringquartet.biz/web/images/fck/file/86441559320.pdfIn PDF document text
    • http://tlproduct.com/userfiles/file/51450004253.pdfIn PDF document text
    • https://ytdrive.com/CKEdit/upload/files/wifar.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608309dbd99d5---zofigiva.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/bvqp4h65sef5odq7osmk1cf4aj/79994644664.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160812136c4a32---2868448228.pdfIn PDF document text
    • http://teerosy.com/ipp/images/uploads/files/40113983825.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5ebaa89db6a213c7d3ed70176eb2ef5d/28984698670.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=volleyball+setter+hand+positionPDF 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_off0000e3d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3D1 10712 bytes
SHA-256: 8b311b2649818df21fda014aae311cdfe8866a3a878e0fa1fca06741bfa2239b
font_01_sfnt_off0000fc2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC2A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001143c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1143C 16952 bytes
SHA-256: 196c1dca291988086ab7ab4c53ba484a781199ecdea1e681fb6f00710bd32675