Malicious PDF — malware analysis report

Static analysis result for SHA-256 571bd5ec542ef0cb…

MALICIOUS

PDF

75.0 KB Created: 2021-06-19 19:46:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 7038646edd4b30320aaa139e9c1c9bf4 SHA-1: 3e74f97b4fa8baf8e84f0b82a44b0e6ff655980b SHA-256: 571bd5ec542ef0cb17b6f8489dded1ca30e1efaaef4ff0c47dea56a16e3a55a1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as Pdf.Phishing.Trojan. The numerous embedded URLs point to compromised WordPress sites, suggesting a link farm used to distribute malicious content or facilitate phishing. The document body is heavily obfuscated and unreadable, but the presence of external URIs and link farms indicates an attempt to redirect the user to malicious destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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://infrive.ru/uplcv?utm_term=can+my+tortoise+eat+tomatoes PDF link annotation
    • https://www.endthestigmacounselling.com/wp-content/plugins/super-forms/uploads/php/files/vt1k34csgibevdivbc3fgpgam7/72009868177.pdfIn PDF document text
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/e52e17fcc594b198e26f69ef396639c1/40788978055.pdfIn PDF document text
    • https://inchirierielicopter.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607f79f334b83---pamuxej.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609228fee9e09---3946338982.pdfIn PDF document text
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/pp1lq12hjd6958k3avup36qe3n/tanetuwupize.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/160933a244b8b0---9986606324.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/91bingsbd8gf5q4og57skoeuv3/34790524979.pdfIn PDF document text
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ca994a124c---30172802015.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160aea31d71126---23133296884.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c550f7d0974---vevixepebupozudaxipinekew.pdfIn PDF document text
    • http://tfh-filter.hu/_user/file/38546796556.pdfIn PDF document text
    • https://masihpt1.com/contents//files/72221506881.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/42e067645bf0f769a8237760ae880622/73135212342.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607f4d85a346d---81452557815.pdfIn PDF document text
    • http://to-tuong.com/media/ckfinder/files/27038979081.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/t8rcoutj0eq5cttek8neooh9fq/juritolin.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/c6f5901011a508618830faf16f7453f9/nawekeduli.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e9e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9E9 4808 bytes
SHA-256: 6e4d04dbb044b70c1c703a4bd3ce6606831d01abc819a928d2b6a051c782dc9e
font_01_sfnt_off0000fa2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA2A 10784 bytes
SHA-256: 9e0e6d11ad11aabed8278861082178e5bb35be058a21148eddb1ddeefc38aa50