Malicious PDF — malware analysis report

Static analysis result for SHA-256 b53ad45e261e9f60…

MALICIOUS

PDF

66.5 KB Created: 2021-06-18 08:16:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 2874e076540370c4be02c993b9788660 SHA-1: 8823bf07f7357a2ae517a76795321870d5194805 SHA-256: b53ad45e261e9f608c7dd7b90e0df71a4192c93d3e973f4cac56e19f27ce6962
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious. It contains a significant number of external links, many pointing to compromised CMS upload directories, indicating a link farm designed to distribute malicious content or phish users. The document body is heavily obfuscated and contains metadata suggesting it was generated by wkhtmltopdf.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/160a0642a83897---52547784104.pdf In PDF document text
    • https://bayardplaza.co.uk/wp-content/plugins/super-forms/uploads/php/files/vurfbnng3qv4o64kaq0ka9un71/56010414730.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c00b0e070a3---wadafaxotoromumub.pdfIn PDF document text
    • http://www.bash.cl/media/file/82261802282.pdfIn PDF document text
    • https://accuratesearch.com/userfiles/file/26828569230.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c31697dbaba---bulawi.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081329eb1ea1---99102289557.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1609764d40d574---gewukuzivitobanu.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/012ff2bd0570b8c63bc63c021e8b91e4/26012080644.pdfIn PDF document text
    • http://lbhs1965.com/clients/6/6b/6bdd8f708684a1f547efbf97e1630fe5/File/43795792811.pdfIn PDF document text
    • http://agendaalzheimer.org/files/galeria/files/fovabitazajana.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16081c234c999a---getomise.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/c42d5b956f7750109fa2c9063a8530e9/49691320763.pdfIn PDF document text
    • http://stevis.cz/files/file/rifawarivad.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=bangla+gaadi+jhumke+kangna+mp3+songPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c3b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3B0 5628 bytes
SHA-256: daefb8959f0e4dcdbb450db6da11e7b35bd026e9275a43ef78d8376e9e459c65
font_01_sfnt_off0000d6b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6B5 11276 bytes
SHA-256: 5754ef3816098924bcb5d37c1caf8f1dd5d90ef579f6f890dc61492c2572455b