Malicious PDF — malware analysis report

Static analysis result for SHA-256 af898df41547cb6d…

MALICIOUS

PDF

88.9 KB Created: 2021-08-07 16:56:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 245a53ce358d9dc7642c40f679d55906 SHA-1: 35b83baec620f747e42c87e957d258668029232b SHA-256: af898df41547cb6d642c2e51fff98a2e86e1cba6de4bcc566da2e3083dc0f712
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, identified by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious content or phishing pages. No scripts were extracted, but the structure itself is designed for redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160b84a0c60490---xapowurej.pdf In PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099e8b2e7b68---91479939620.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1608f19c9cba67---bodojetinaku.pdfIn PDF document text
    • http://kredoteka.ru/uploads/file/84992413955.pdfIn PDF document text
    • http://pngroup.pl/ckfinder/userfiles/files/59172158592.pdfIn PDF document text
    • http://ucity1967.com/clients/f/f9/f95c10655bf48216a4b8c8e4321ec146/File/virafisa.pdfIn PDF document text
    • http://riggi.ru/userfiles/file/dorekonaz.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4450c281d5---muzomobete.pdfIn PDF document text
    • http://pcccmiennam.com/media/ftp/file/43093038416.pdfIn PDF document text
    • http://spielundlicht.de/content_provider/documents/files/55509409554.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4cd304485c---64816456389.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/16105bbca24c61---86449905809.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/f82i6p45mvpq3dlhcop1qtqd15/mafigenapuli.pdfIn PDF document text
    • http://www.greenbriarpropmgmt.com/wp-content/plugins/super-forms/uploads/php/files/1d40457c9f82f13dc709f802b10d86e7/17322786323.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160bc51537c849---10105794386.pdfIn PDF document text
    • http://www.sempresaude.net/wp-content/plugins/formcraft/file-upload/server/content/files/160739c38095e2---kuzoxera.pdfIn PDF document text
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/efuo5pkfl4r8la7lo7n0p7c72u/34213725664.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160940f49f3503---18086513884.pdfIn PDF document text
    • http://cdio.vn/uploads/userfiles/file/lizowud.pdfIn PDF document text
    • https://pbchistoryonline.org/uploads/file/11012903942.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/fcce8a36142f40bb6407fe9b9c3c7b7f/24858120084.pdfIn PDF document text
    • http://amadpich.com/userfiles/file/15047233041.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b91e62a7215---bifaxijelonojozunefizolus.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a23aa814961---vokinava.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c021dadb76c---8894328729.pdfIn PDF document text
    • http://tfforming.ru/d/files/5652721713.pdfIn PDF document text
    • http://ggmtc.net/userfiles/files/sanonadiju.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=brain+power+motor+controller+866c-6+manualPDF 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_off0000f748.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF748 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010f5f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F5F 11016 bytes
SHA-256: 673cf1557036ca3a5c12dd119f01d224a5470928d4978a4fd2f141ea973113c1
font_02_sfnt_off0001290d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1290D 16936 bytes
SHA-256: bc56238f9217f6a86f89e3786e2a85dec13fae9e76803030f6a3bd62bb12d9cf