Malicious PDF — malware analysis report

Static analysis result for SHA-256 424f4f6ff819a780…

MALICIOUS

PDF

75.0 KB Created: 2021-09-17 11:15:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: bdb5706493ff28fc64b32fe2388c672b SHA-1: acc7f3d68a5e6a18769adf32c77c432b93a9d400 SHA-256: 424f4f6ff819a780489bb9cce2955d28f95d5709649cef7b73042d6d9c693cbe
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. It contains numerous links, many pointing to compromised WordPress sites, suggesting a link farm or phishing lure. The presence of external URIs and the overall structure indicate an attempt to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.oasipizza.it/wp-content/plugins/formcraft/file-upload/server/content/files/161405b07be633---dupasotesimijisoz.pdf In PDF document text
    • https://datajournonepal.org/files/vemepipizejuwofasij.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/16140cd3448c47---tujifuzamagabagab.pdfIn PDF document text
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/1i7pmps3ufcp6orgo1gnikf5u3/79792601043.pdfIn PDF document text
    • http://stitesattorney.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/12049417024.pdfIn PDF document text
    • http://www.ctmmaximoravenna.com/ckfinder/userfiles/files/1002906363.pdfIn PDF document text
    • http://nrgmedia.hu/files/file/79117164529.pdfIn PDF document text
    • http://aldobini.it/userfiles/files/96820879946.pdfIn PDF document text
    • https://chandrakantmusicacademy.org/ckfinder/userfiles/files/tukilurirolas.pdfIn PDF document text
    • http://gurgaontaxi.com/pa/trainstation/uploads/image/file/wiridaxekijezokawiforomog.pdfIn PDF document text
    • https://saikekanglun.com/filespath/files/20210909182028.pdfIn PDF document text
    • http://tasteofruraleurope.eu/upload/File/2979639059.pdfIn PDF document text
    • http://cwesp.biz/upload/file/gifolotowabamevuxiziribo.pdfIn PDF document text
    • https://venefoil.com/ckfinder/userfiles/files/39314623844.pdfIn PDF document text
    • https://cosmopolitanhotelbg.com/uploads/wysiwyg/files/15758628148.pdfIn PDF document text
    • https://gilbertems.com/videos/file/74332171061.pdfIn PDF document text
    • http://shopcloud.cloud/ckfinder/userfiles/files/natepegimotidipixamok.pdfIn PDF document text
    • http://potlista.com/file/files/74533224328.pdfIn PDF document text
    • http://kargiskola.ge/myadmin/ckeditor/ckfinder/userfiles/files/90225326918.pdfIn PDF document text
    • https://thietbivesinhanhhuy.com/asset/files/37449193044.pdfIn PDF document text
    • https://inarsindbari.org/uploads/fusijunonosev.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/161315c2c27ef1---nuxes.pdfIn PDF document text
    • http://dasbluemchen.com/64774766207.pdfIn PDF document text
    • https://vinaconexmec.vn/uploads/news_file/41794272508.pdfIn PDF document text
    • https://apexsafetyproducts.com/ckfinder/userfiles/files/26461996619.pdfIn PDF document text
    • http://mdfgiare.com/upload/files/nasaxuvafokasam.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=free+web+series+streaming+appPDF 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_off0000c25a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC25A 16768 bytes
SHA-256: 113b6c9d002c7aa491b7ee994a3f99d10c34554a19a553a7f479ee346f8da134
font_01_sfnt_off0000ed81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED81 10632 bytes
SHA-256: 1f22790b294021c78b501e5a424fb69771935d927a1f12997b06a79528efee5f
font_02_sfnt_off000105b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105B1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1