Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4d65e14e5509c50…

MALICIOUS

PDF

75.2 KB Created: 2021-09-08 14:14:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 857b6ff67c4562ade6b9bde3934d61d8 SHA-1: da4a768ec3ac7ed7f5e54dbb48574cef21f94b70 SHA-256: d4d65e14e5509c5068e3e54df63e52a01c2398694710e64ee60fd999641bd025
96 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised WordPress sites, indicating a link farm or SEO manipulation tactic. The ML classifier also strongly flagged this PDF as malicious. While no scripts were extracted, the structure and URL patterns suggest the document is designed to redirect users to potentially harmful content or exploit kits.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://b7b.reviewz.eu/app/webroot/files/userfiles/files/2885654518.pdf In PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613424fd46845---lexazamug.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612ec31616a26---gejimebeka.pdfIn PDF document text
    • http://combatkuntao.com/ckeditor/ckfinder/userfiles/files/jotitazoxexananin.pdfIn PDF document text
    • https://inprovitchile.com/ckfinder/userfiles/files/80629614791.pdfIn PDF document text
    • http://www.libroparlatolions.it/backoffice/ckfinder/userfiles/files/92157102272.pdfIn PDF document text
    • https://2winit.com/Files/files/14816390355.pdfIn PDF document text
    • http://www.hausman.eu/images/wyswig_images/file/wosoxix.pdfIn PDF document text
    • http://ammk.sk/userfiles/file/sojikodewuverilaxejo.pdfIn PDF document text
    • https://laflammerouge.ch/userfiles/files/zutekirogewosemivuvu.pdfIn PDF document text
    • https://al-wesam.com/userfiles/files/96117108506.pdfIn PDF document text
    • https://drddvichitra.com/userfiles/file/76650066538.pdfIn PDF document text
    • https://growyourmoney.in/userfiles/files/dakaxajenavenumuk.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/8c7556bbd2b403f67630bff713c120c1/9030307171.pdfIn PDF document text
    • https://novinfasteners.com/userfiles/file/63437155024.pdfIn PDF document text
    • http://asia-test.informacittadino.net/media/files/2716981655.pdfIn PDF document text
    • http://robedecreateur.com/img/files/fagidekawuwat.pdfIn PDF document text
    • http://cbelmira.com/wp-content/plugins/super-forms/uploads/php/files/c579cba8aafffdc03eb7d617313b6dee/kikube.pdfIn PDF document text
    • http://gardenofsound.com/userfiles/files/pudoxa.pdfIn PDF document text
    • https://sindicav.com.br/ckeditor/ckfinder/userfiles/files/75000033782.pdfIn PDF document text
    • http://www.serenissimaservizi.com/files/jedudatuluweno.pdfIn PDF document text
    • http://ackerviewguesthouse.com/userfiles/file/31667342830.pdfIn PDF document text
    • http://gewidor-gmbh.de/uploads/files/wogananin.pdfIn PDF document text
    • https://psychologgia.pl/Upload/file/29208284692.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=gramatica+coreana+en+espa%C3%B1ol+pdfPDF 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_off0000b750.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB750 11028 bytes
SHA-256: 79efec07cc4fc73dceb43eec144ecc904e6498c89669760dc3f95da056ada172
font_01_sfnt_off0000d0bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0BD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e8cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8CF 20160 bytes
SHA-256: 0961db9d6e42ae59f6ef0659f5444104cb865502cf6ee82103f00dca91036042