Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bafc66a5feb0da6…

MALICIOUS

PDF

84.2 KB Created: 2021-08-18 15:24:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 09bbf89edfc872d53777a6a3015afd3a SHA-1: 95eead31744383178a070a4a1847bcbcc74fe95d SHA-256: 8bafc66a5feb0da679d61e983e5c8af63d06d1a8de94d67c3567cde5083dd57a
96 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised WordPress sites or disposable hosting. The ML classifier strongly indicates maliciousness, and the heuristic firings suggest this PDF is a link farm designed to redirect users to malicious content. The presence of multiple compromised CMS upload links further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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://zlatartopalovic.rs//files/71962630737.pdf In PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/cd7bb603c2ad34fef57aaa53679a3dbf/31473970009.pdfIn PDF document text
    • https://www.burit.net/wp-content/plugins/formcraft/file-upload/server/content/files/16089e67a0fe42---32137158141.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c2546b7ff8e---96541992895.pdfIn PDF document text
    • http://homeopathyhk.com/files/93818662465.pdfIn PDF document text
    • http://suarezbeltran.com/aym_images/files/48650675672.pdfIn PDF document text
    • http://dichvuhangngay.vn/uploads/image/files/31223261130.pdfIn PDF document text
    • http://www.gdchgs.com/admin/img/files/97460811747.pdfIn PDF document text
    • http://thienminhgroup.com/uploads/userfiles/file/30876219800.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16094a7492bee8---xesunutitixefuramafeleju.pdfIn PDF document text
    • https://armagedonspedycja.pl/files/file/motunupejamexojabu.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b6faf24bc62---81367390252.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/336aaffb8582d671c7e310479b0de8e1/12547771916.pdfIn PDF document text
    • https://prevodi-plovdiv.com/userfiles/file/55015462475.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160810a0f7c4dc---17854024615.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/1608b015c1bf21---90883899291.pdfIn PDF document text
    • http://www.loicadesacavem.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16086f7b344bd8---55871218583.pdfIn PDF document text
    • http://beiks.info/public/file/20316982284.pdfIn PDF document text
    • http://aatmicscience.org/asuserfiles/file/ganezibasujireso.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bef7d1c370a---5983631524.pdfIn PDF document text
    • https://hopadive.cz/ckfinder/userfiles/files/90080632348.pdfIn PDF document text
    • http://nage-z.com/ckfinder/userfiles/files/fugakig.pdfIn PDF document text
    • https://roc.mn/uploads/files/29102553019.pdfIn PDF document text
    • http://rgn2u.com/userfiles/files/72788455178.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=banco+popular+de+puerto+rico+hipotecas+telefonoPDF 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_off0000e450.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE450 10872 bytes
SHA-256: b806ecf1ed84bc2d8f3d8c234efbf754d30c822494145784b5c202cd58fa22d3
font_01_sfnt_off0000fd67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD67 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011579.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11579 17936 bytes
SHA-256: fa1b194491a8e539228d2e77cc1de8cefe6fbe79c05fadf379ce756d5e4e2e5b