Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b4d4d3b22838cc3…

MALICIOUS

PDF

84.9 KB Created: 2021-09-02 09:05:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: ec9e126f58e4ca6d37bf8c1693c582c5 SHA-1: 2510e44227120eb180f401c92c2a7c1b64274d98 SHA-256: 4b4d4d3b22838cc3be2e499fdde4b92fa39c9a6d4620054f05accadb668ef64a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to disposable hosting or compromised CMS upload directories, suggesting a link farm or phishing lure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to deliver a secondary payload or facilitate phishing. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document designed to trick users into downloading further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9902

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 http://olgapolyakova.com/files/files/semusoxukirirebop.pdf In PDF document text
    • https://susta.vn/userfiles/file/gugatidodovamedeb.pdfIn PDF document text
    • http://cutskytools.com/d/files/mepim.pdfIn PDF document text
    • http://citadelcaralarms.com/userfiles/file/litozetibivutamulugonoba.pdfIn PDF document text
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/c86a436e10e6193f2378a9a2d3ec990b/89020047914.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d57a7642ab---lofadafodafosanuw.pdfIn PDF document text
    • http://guanzhuli.com/userfiles/file/40133866120.pdfIn PDF document text
    • http://wallacewilliamsfamilyreunion.net/clients/6/66/662ca4338cd1fa41fa93b88222973dc6/File/42766594006.pdfIn PDF document text
    • http://kondicionery-vidnoe.ru/upload_picture/file/bigazesa.pdfIn PDF document text
    • http://studiotecnicobonoli.com/userfiles/files/23548505567.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/160872f5937877---lebip.pdfIn PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc22f0b7f7f---dilatevejumov.pdfIn PDF document text
    • http://vetranhtuong.info/luutru/files/mulixuwuliwolew.pdfIn PDF document text
    • http://alfonsoguiggiarchitetto.it/userfiles/files/13529454602.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c2a84e3988e---vigapol.pdfIn PDF document text
    • http://gphs84.com/clients/866382/File/sasuruzusupipizewasereb.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/dec66c6979df5a8dd57b309c5e123fb4/fujupoperitobekefidema.pdfIn PDF document text
    • http://schmetterlingsgaerten.de/file/60591243113.pdfIn PDF document text
    • http://madinaboys.com/easydo%20v2.00/files/uploads/kakujiwu.pdfIn PDF document text
    • https://www.businesswatchguardingservices.co.uk/wp-content/plugins/super-forms/uploads/php/files/nne3fd1cav1gafbroqpht54qk1/20279039843.pdfIn PDF document text
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c45a6bbb443---46253586255.pdfIn PDF document text
    • http://sapaelitehotel.com/webroot/img/files/70783376492.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160af6c9dc6f0b---lezatu.pdfIn PDF document text
    • http://newtarrytowndeli.com/uploads/files/90843669848.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/16080e7bd9ffa1---28380860738.pdfIn PDF document text
    • http://farmina.ru/uploads/files/negaju.pdfIn PDF document text
    • http://acpiindia.com/userfiles/file/37909240363.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=trading+and+profit+and+loss+account+excel+formatPDF 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_off0000e3e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3E0 17660 bytes
SHA-256: 474ea2cc0a66a6fc844a3d81fc73030624041da586e9d18d4ec1a4459620b012
font_01_sfnt_off0001122e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1122E 11128 bytes
SHA-256: fb36eb0fbc41b214837e65c48eb388c02572b8216e8f511057cd9caecd7cbace
font_02_sfnt_off00012bfb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BFB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1