Malicious PDF — malware analysis report

Static analysis result for SHA-256 856c772d64ed01f3…

MALICIOUS

PDF

67.7 KB Created: 2021-06-22 18:55:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: dbe540800e4fdc7a7d8b2addd8a38b85 SHA-1: 57b51c21937171d6e9c5ca493dd4ff7113640eea SHA-256: 856c772d64ed01f369432896df3a59418a0ab8d95d262a8cc151c01fc234457d
164 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, specifically as a phishing trojan. It contains numerous links to compromised websites, likely intended to host or redirect to malicious content. The presence of a 'download button' lure further supports a phishing or social engineering attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://irlanc.ru/uplcv?utm_term=smith%2527s+general+urology+pdf PDF link annotation
    • http://travelport.pl/userfiles//file/78927761423.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609340fda2af9---vuwemumefujebuberido.pdfIn PDF document text
    • http://sjhrz.com/images/upload/File/bogefabidol.pdfIn PDF document text
    • http://hoteldazegliotorino.com/userfiles/files/16751856589.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/ff72ec4abba5152b5b56eeef34075932/96641403118.pdfIn PDF document text
    • https://xn--mgbaf4adbs1bd2i.net/upload/ckfinder/files/zagowudusedezinewafobegiw.pdfIn PDF document text
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/0a7db959221e44b76ae2fa3fe80f7ac9/6840699237.pdfIn PDF document text
    • https://mindweave.co.uk/wp-content/plugins/super-forms/uploads/php/files/o9dvtdk0aeu5ds16e38njshegc/mojiguremabuvivavede.pdfIn PDF document text
    • https://qualitymattressfactory.com/admin/userfiles/file/43634880685.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/8a0b0ea0696fe2da85ed495d7abfe27c/45612246756.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/7fj2aej16lkv2070p4kp950rq7/203975418.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095c8bbd43c8---fewexokavikomi.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1608f5ec563801---15756295237.pdfIn PDF document text
    • http://www.justgiveahand.org/wp-content/plugins/formcraft/file-upload/server/content/files/16084f4934e953---nilera.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_off0000c9f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9F9 5696 bytes
SHA-256: fdc9c6cb72fc96b719b0d4606784a4645baf9daae25b324b0cd69a45c8d52500
font_01_sfnt_off0000dd3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD3B 10792 bytes
SHA-256: dbcc59ef63c48443cbc2e50944eeb3c1a952b0b7729d6cad8e407ad7cdaef1e6