Malicious PDF — malware analysis report

Static analysis result for SHA-256 86c36fd58711b093…

MALICIOUS

PDF

66.6 KB Created: 2021-05-24 14:36:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 532ba7581ba7455035c237d485efcf11 SHA-1: 7ea7bf547142bc8c162c6d0de3c6d882ce04a764 SHA-256: 86c36fd58711b093894fb61817d774b4a3081650207fa982ba35850d8642a0e9
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, specifically as a phishing or trojan delivery mechanism. It contains numerous links to external websites, many hosted on compromised WordPress installations or disposable domains, suggesting a link farm designed to redirect users to malicious content. The embedded URLs and the overall structure indicate an attempt to deceive users into visiting potentially harmful sites.

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=ejercicios+de+objeto+directo+e+indirecto+pdf PDF link annotation
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/b1a6a4216a5b25e907b7d5d6ffc3cb05/78355963006.pdfIn PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/28b0396bacde7266ab9ab24dff9046fa/71475661420.pdfIn PDF document text
    • https://alternativecarrepair.com/userfiles/file/83450303314.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/a177f285321dab9f50b354a3d63b8950/73986573228.pdfIn PDF document text
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3fffe1151---19189485266.pdfIn PDF document text
    • http://bendhorseride.com/userfiles/file/tikusipazodevozagulipix.pdfIn PDF document text
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/96380894398.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16079a3511baad---xuberuxuxagovesovelevof.pdfIn PDF document text
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/ddafdaafa41ff252154a8557fa19a036/zinusivinatalosaka.pdfIn PDF document text
    • https://fanaf.comarticle_ressources/file/37725601833.pdfIn PDF document text
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/jilq83rml3fu3h408jo2rb7j85/13246548608.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c3eac3fd06---wejivone.pdfIn PDF document text
    • http://blog.crowdly.com/wp-content/plugins/formcraft/file-upload/server/content/files/160963374aac00---75205598505.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1607d9435d3c2d---6493440254.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/8134bd838efe617795c7771dfdc09cd0/34007703423.pdfIn PDF document text
    • http://agnieszkapawlik.com/userfiles/file/kiwopajubujusetimarokorub.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_off0000c85e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC85E 5080 bytes
SHA-256: 75d282a00b8023cee4197951fe2a502239a6f03ac10bd715a217ca017062ed9e
font_01_sfnt_off0000d9b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9B9 11116 bytes
SHA-256: afdf445ea8528347943d8fca9503e4c5364ac3f44438f5bb3e676d868a40b3f3