Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c1e1254ebac0088…

MALICIOUS

PDF

84.0 KB Created: 2021-09-05 03:20:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 1a395cc06b35e0c9ac874cddd6fb21ab SHA-1: 133cc97b40b6285a05c2bf98a72d0b35af18baa1 SHA-256: 8c1e1254ebac0088e5eb21eda35227b17f1512d4a3f8e09b6fca0ebb3c0f2e37
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. The file's structure and URL patterns suggest it functions as a link farm designed to obscure the ultimate destination of the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://dewalt-naradi.cz/media/upload/editor/file/xaduwebigulorawakaj.pdf In PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c0c8a4bd98c---57719000764.pdfIn PDF document text
    • http://terminsk.by/pics/files/vetuwugefe.pdfIn PDF document text
    • http://ambulanceservice.pl/userfiles/file/72072443679.pdfIn PDF document text
    • http://wccflooring.com/userfiles/files/zusasuzi.pdfIn PDF document text
    • http://schokozentrale.de/idata/46356288482.pdfIn PDF document text
    • http://wenxuezj.com/images/File/68924879328.pdfIn PDF document text
    • http://rhondadejean.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/bapadebajujorazubobiridam.pdfIn PDF document text
    • https://nowbali.co.id/wp-content/plugins/formcraft/file-upload/server/content/files/1606ed49b76d87---nusuvenobi.pdfIn PDF document text
    • https://srilangkapools.com/contents//files/tabogi.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/56633997670.pdfIn PDF document text
    • http://beccaro.it/userfiles/files/duwosekamunonufuvupi.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/lgm86o4ua9a9gasd8107tsdejo/bapolelujapaxab.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/7adfo6260evja70vnej5sorq5u/lesisulutegemexelulugelem.pdfIn PDF document text
    • http://iwilldoit.ru/uploads/files/files/vowepexexefarepamaxa.pdfIn PDF document text
    • http://carrollcountylawyers.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/98676783974.pdfIn PDF document text
    • http://cgpreceptor.com/ckfinder/userfiles/files/40099193392.pdfIn PDF document text
    • http://domholidays.com/userfiles/file/fonavukunikosoxitiledo.pdfIn PDF document text
    • http://yunnanyingxiang.com/ckfinder/userfiles/files/62637272747.pdfIn PDF document text
    • https://micro-logic.ro/images/uploaded/file/80191706362.pdfIn PDF document text
    • https://frontiersneurophotonics.org/wp-content/plugins/formcraft/file-upload/server/content/files/1/160aa2dfa2840c---leligefifusudogupad.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/160804fdf1cd67---damosenuvofan.pdfIn PDF document text
    • https://pelicanfinancialnetwork.net/ckfinder/userfiles/files/surol.pdfIn PDF document text
    • https://alixdemassy.fr/userfiles/file/wagap.pdfIn PDF document text
    • https://hostessima.pl/userfiles/file/10738683012.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085b8fa12451---79990503740.pdfIn PDF document text
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608fbb63efdfd---71427382843.pdfIn PDF document text
    • http://potlista.com/file/files/nazimiri.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=scert+up+primary+books+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_off0000e35c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE35C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fb6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB6E 17252 bytes
SHA-256: 03555bb5e9cbec53f6a7bb7f77c97bdb0a0cb1afb4e005ed80ad7c6366c91cda
font_02_sfnt_off00012819.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12819 11152 bytes
SHA-256: 1a19ea8f06f19ac539784c7e9738f1981720e6aafa2f44574151ead43bf4183b