Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cf1600e907929f4…

MALICIOUS

PDF

77.4 KB Created: 2021-09-05 12:48:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 69b90da259ddd2d309d8a64c33da7e42 SHA-1: 47e1ebe360f29445cf23ae2b601080138a6835b2 SHA-256: 4cf1600e907929f4a22550f263cd4b082a220ca31c4ada53040b05cb17a58836
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to various domains, many of which appear to be compromised or disposable hosting. Heuristics indicate it functions as a link farm, likely intended to redirect users to malicious content or phishing sites. The ML classifier and ClamAV detection strongly suggest malicious intent, consistent with phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://nomylo.ru/uplcv?utm_term=heim+kratzer+semantics+in+generative+grammar+pdf PDF link annotation
    • http://ykzn8.com/upfiles/editor/files/bofupu.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072283573cb9---fenuwasebowuzobegevipevef.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160811792d0186---kedigano.pdfIn PDF document text
    • http://miele-service-center.ru/uploads/files/tobag.pdfIn PDF document text
    • http://solamsys.com/userData/board/file/bifola.pdfIn PDF document text
    • http://dok-vo.ru/userfiles/file/16780973640.pdfIn PDF document text
    • https://fratellifurloni.it/file/12303828853.pdfIn PDF document text
    • http://phantasos.org/userfiles/file/98305102773.pdfIn PDF document text
    • https://steammining.com/userfiles/file/xokorefajamakofu.pdfIn PDF document text
    • http://grandp.ru/userfiles/file/taminizijegevatulo.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/160bbc7b69341e---77024966758.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607ddedc82c3d---96057786095.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607df552e46a2---woganewopuzumolujofesa.pdfIn PDF document text
    • http://mtecommerce.it/public/news/file/20781346815.pdfIn PDF document text
    • https://www.federatedlighting.com/wp-content/plugins/super-forms/uploads/php/files/0b5f00cea0eceb1dc276d2057902fc8c/beboxonewelofabokewi.pdfIn PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610b70bb281c1---sevapobubotatiwemexi.pdfIn PDF document text
    • http://martom24.pl/martom/userfiles/file/23399178030.pdfIn PDF document text
    • http://szwygs.com/upload/98280936229.pdfIn PDF document text
    • http://fashionflutters.com/ckfinder/userfiles/files/36447936117.pdfIn PDF document text
    • http://rivieahk.com/clients/5/51/51325344bd1517f257d6959d5350918e/File/fofikegipivijuxupedisiju.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_off0000c6bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6BB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ded2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDED2 11004 bytes
SHA-256: 730bd13e0ce9885a0e32e60aefcb87ac9a0716b3caf88d216b1482aa9186b38a
font_02_sfnt_off0000f836.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF836 17860 bytes
SHA-256: ea4b170a40c911b4234b69f885b220e7ae86a12cc864547bd0a6ced96ac0c946