Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c5b0d5917fe1978…

MALICIOUS

PDF

77.7 KB Created: 2021-06-13 07:43:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: f3bf2ecb2dcf2893be57c23e5e4ec2c8 SHA-1: fb96503082a8d638412b054c29e4f20698650d3f SHA-256: 4c5b0d5917fe1978b820ad2a7516935a51105016fe71c0b3450859021fe66f00
156 Risk Score

Malware Insights

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

The PDF file contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to direct users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://nomylo.ru/uplcv?utm_term=gk+questions+and+answers+mcq PDF link annotation
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/9496a66aa68b3b20b54bfec353278291/sukopapalekalatediro.pdfIn PDF document text
    • http://mesterek.net/tmp/90498852757.pdfIn PDF document text
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a732b149cc3---sozatot.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1608bf17f21644---25600241184.pdfIn PDF document text
    • http://akkoryazilim.com/userfiles/file/72674566421.pdfIn PDF document text
    • https://www.eoluk.com/wp-content/plugins/super-forms/uploads/php/files/leef4fhg6kjb1hssfbsmhc25ed/82920090538.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/160ac69969c78e---defujorogani.pdfIn PDF document text
    • https://chefinhogourmet.com/wp-content/plugins/super-forms/uploads/php/files/c8b1a063d2e0afcd08d956bd6d072a3c/97476572541.pdfIn PDF document text
    • http://www.sempresaude.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606ebaba31a65---ranakulokexujazaxerasopi.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160879f3077f25---50094224587.pdfIn PDF document text
    • https://jetaime-shop.com/files/30184743154.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/ad08dcb38ee3df1580dde324ed58004a/10692936454.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609b0eb36a00d---pajagogatimo.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/16095107f41f1e---biwivuw.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/fhtguqab5qs4lvodnsqjgqunqi/75760249378.pdfIn PDF document text
    • https://carstenrath.com/wp-content/plugins/super-forms/uploads/php/files/suuvc4pffi7q2hlno9gnsn4ns5/86308078801.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ea96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA96 5364 bytes
SHA-256: 9ac32e0b43c8cced5d478bdac0f31ec90f3ff4dab53e7ce1fd30f4201bde21f0
font_01_sfnt_off0000fcd3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCD3 1728 bytes
SHA-256: 0810ce0371bb48a6dbbb6c56d423a1e4bda4455f4638deeed9c91ec23a796c96
font_02_sfnt_off0001056b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1056B 10720 bytes
SHA-256: 0fd25fb24b19db8f1d8e4770d99d36037ad158d5cc6a4990ae7b7428c1a4a6ad