Malicious PDF — malware analysis report

Static analysis result for SHA-256 00c4fba4bd4d6a20…

MALICIOUS

PDF

78.1 KB Created: 2021-09-17 08:47:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 14cf7c42c5e80769c0e8233509b8da44 SHA-1: 2deee5548b08bfe6af3c7ae7f66312b6611574f2 SHA-256: 00c4fba4bd4d6a201aacad0502b1003210f26df1b8d0449bb92c66758deaf313
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded URLs, many of which point to disposable hosting or compromised WordPress sites, indicating a link farm or redirection scheme. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the nature of the URLs suggests a potential for delivering malicious payloads or phishing attempts, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://chcial.ru/uplcv?utm_term=unblocked+games+72 PDF link annotation
    • http://dichvutot99.com/webroot/img/files/rimidodosovamevo.pdfIn PDF document text
    • http://bigcool.net/webroot/img/files/digozosemubarurifubu.pdfIn PDF document text
    • http://plncse.hu/php_data/file/59173642992.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/1613d756baa1de---godewixuwobib.pdfIn PDF document text
    • https://apra.pl/files/file/bujekakefatagoku.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/e2ac7f4f5d341bf73d41f0ce5ef2d5ce/fegeleberigud.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bda67e0514---91934616249.pdfIn PDF document text
    • http://dirpub.org/editor/ckfinder/userfiles/files/23569672402.pdfIn PDF document text
    • https://luyenthitoeic.info/userfiles/file/takawajavimonagozexakawev.pdfIn PDF document text
    • https://cleanenergy.mn/uploads/files/xulubevamivibatogagef.pdfIn PDF document text
    • https://feldmann-spedition.de/pics/userfiles/file/1239378464.pdfIn PDF document text
    • http://oppedisanorobertosrl.com/userfiles/files/18727088285.pdfIn PDF document text
    • http://nutronicltd.com/userfiles/file/bukakemode.pdfIn PDF document text
    • http://impactpluslearning.com/ckfinder/userfiles/files/72926158748.pdfIn PDF document text
    • http://eaas-journal.org/survey/userfiles/files/5735645388.pdfIn PDF document text
    • https://s-serviss.lv/userfiles/file/pusakavivemotaxizijenuj.pdfIn PDF document text
    • http://sanfrancescovet.com/userfiles/files/kavutalenulax.pdfIn PDF document text
    • https://libertyrealestate.in/ckfinder/userfiles/files/xugawokine.pdfIn PDF document text
    • https://vildmarksjagt.dk/userfiles/file/24424419119.pdfIn PDF document text
    • http://iucecb.com/files/file/pofug.pdfIn PDF document text
    • https://proetcontra.hu/userfiles/file/35476178577.pdfIn PDF document text
    • https://mwasafat.com/uploads/files/11024528073.pdfIn PDF document text
    • https://ketex.com/trcgp/ckfinder/userfiles/files/47329451837.pdfIn PDF document text
    • http://usmleworkout.com/files/file/75795258662.pdfIn PDF document text
    • http://marcobernini.it/userfiles/files/26855557772.pdfIn PDF document text
    • http://yasairamenbar.com/uploads/files/87486423745.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_off0000cc72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC72 17468 bytes
SHA-256: 5690f7790d9dd27b011f23ed68cf78f1de31a0928469320299c09d7e67bcb055
font_01_sfnt_off0000f9ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9EC 10832 bytes
SHA-256: 344295080d304cc4d2646ef4ccef793fc52c78920fe1d2587fc74f0ae6b099c7
font_02_sfnt_off000112d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x112D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1