Malicious PDF — malware analysis report

Static analysis result for SHA-256 21c1a8d3915ebfff…

MALICIOUS

PDF

76.9 KB Created: 2021-05-09 19:23:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: c8b4fcc683e58ab8c32d6fe67d5c0813 SHA-1: d58c1826b36ea305781c800361bf7889743301ec SHA-256: 21c1a8d3915ebfff0a2cbbbf3a1097da261e98829a8f2be98b69ac3ff605cb92
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, indicating a link farm or redirection scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The embedded URLs and the nature of the link farm suggest the document is designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://jottigo.ru/strik?utm_term=how+to+bypass+zone+dsc+alarm PDF link annotation
    • http://virnet77.ru/52171788958jtclh.pdfIn PDF document text
    • http://safijejog.mygamesonline.org/10250378059.pdfIn PDF document text
    • http://wow50.pro/72190985001ggfmp.pdfIn PDF document text
    • https://cdn.sqhk.co/jiluputumusi/eKgfWwS/40542694898.pdfIn PDF document text
    • http://about-central.com/71754406729mkr2h.pdfIn PDF document text
    • https://cdn.sqhk.co/gizivapejoko/dJ3gQhh/memento_mori_gdr.pdfIn PDF document text
    • http://successinyourlif.website/yoga_mudra_information_in_english22fv8.pdfIn PDF document text
    • http://mavaxur.mywebcommunity.org/arduino_uno_francais.pdfIn PDF document text
    • https://cdn.sqhk.co/peluxisomex/djijhar/25414236984.pdfIn PDF document text
    • http://austritkfa.com/what_is_non_woven_fusible_interfacingrfx3j.pdfIn PDF document text
    • https://cdn.sqhk.co/letinumi/sY0hfbR/30678141008.pdfIn PDF document text
    • https://cdn.sqhk.co/tegatiwuwax/jjEjh6m/gutes.pdfIn PDF document text
    • https://cdn.sqhk.co/xojelumegasi/hejjibk/fazojabewugagopuv.pdfIn PDF document text
    • https://cdn.sqhk.co/nedovipirumu/vvahiEJ/46574117340.pdfIn PDF document text
    • https://cdn.sqhk.co/nopawuwam/P8Aig7D/mashup_songs_meaning_in_marathi.pdfIn PDF document text
    • https://cdn.sqhk.co/manuguwe/ZwXEajg/kigibemilu.pdfIn PDF document text
    • https://cdn.sqhk.co/levowexesu/gjidojd/gowotofikefivisokatu.pdfIn PDF document text
    • https://cdn.sqhk.co/bikegola/gdnhiXl/bollywood_dance_songs_2020_youtube.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://850a36a1-966c-46c3-86ed-e15bcb5778a7.filesusr.com/ugd/ede58b_8f0fff867b7140f18e6450257926381a.pdf?index=trueIn PDF document text
    • https://9f53eded-325d-4e02-8430-7c09bd872488.filesusr.com/ugd/e04405_1adaab52d51b4cb68c2a8dcb4ec12f7f.pdf?index=trueIn PDF document text
    • https://204833c8-abda-4421-8777-5048ee7dd919.filesusr.com/ugd/e30b7a_833daad2d6be45b99ba186ba49b3e8ab.pdf?index=trueIn PDF document text
    • https://c8f6a2ed-bc8a-4fd4-b26a-19707db7c4cd.filesusr.com/ugd/1cc7e8_79298f49646043908fe76da43fdfb344.pdf?index=trueIn PDF document text
    • https://8ed62699-7d02-4439-b935-4286882ef7d4.filesusr.com/ugd/229b11_2c64344a4cff4993897958008ea53bed.pdf?index=trueIn 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_off0000e0a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0A3 5304 bytes
SHA-256: 12f7678b6d542d1765e50df1f309351e913d6b79af8524429f528fe8dab4c0ea
font_01_sfnt_off0000f29c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF29C 10924 bytes
SHA-256: 50455306ddf4a1e2566c027668c6350568d5da89f2bffbe5bf4b33cc5c2523c0
font_02_sfnt_off00011809.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11809 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3