Malicious PDF — malware analysis report

Static analysis result for SHA-256 f164356a80996135…

MALICIOUS

PDF

89.8 KB Created: 2021-01-23 00:42:57 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-17
MD5: 9238b3ca8164bcf8b606277fa08889ce SHA-1: c4009a663a1de2dd07c6b42fe7c37a8682693258 SHA-256: f164356a80996135fdb3f596626996162798d4fdbce8bf7082b5b735d2127c83
244 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to disposable hosting and redirectors, indicating a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. The embedded URLs and the heuristic firings for malicious redirectors and link farms are the primary indicators.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/123?utm_term=hydrogen+peroxide+medical+miracle+pdf In PDF document text
    • https://cdn-cms.f-static.net/uploads/4482618/normal_5fda84371724f.pdfIn PDF document text
    • https://cdn.sqhk.co/kixarozikej/vWcifhd/zaxodagodonekinoni.pdfIn PDF document text
    • https://cdn.sqhk.co/lexebogefaj/ajagjhg/difference_between_gravity_blanket_and_weighted_blanket.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4447658/normal_5fe2e931c78d0.pdfIn PDF document text
    • https://cdn.sqhk.co/bezorufuv/jejfhjc/53856415740.pdfIn PDF document text
    • https://cdn.sqhk.co/femaxozimom/cgiBZyC/drift_wars_gameplay.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4405430/normal_5ffd01d6467d6.pdfIn PDF document text
    • https://nimivisedasefu.weebly.com/uploads/1/3/1/0/131070972/8881573.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4391047/normal_5fd3320719b6e.pdfIn PDF document text
    • https://xepawonim.weebly.com/uploads/1/3/0/7/130776577/zifibimezusapotanaga.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://xozelabudizi.epizy.com/beverly_hillbillies_song.pdfIn PDF document text
    • http://jezowadu.epizy.com/69485583103.pdfIn PDF document text
    • https://s3.amazonaws.com/jonora/76342701364.pdfIn PDF document text
    • http://rovututuxopi.epizy.com/kowogoforufoxefexodex.pdfIn PDF document text
    • https://s3.amazonaws.com/tiluwisulepam/71524325593.pdfIn PDF document text
    • http://temekem.epizy.com/template_for_a_resume_cover_letter.pdfIn PDF document text
    • https://s3.amazonaws.com/divelatoxa/calories_in_lasagna_pasta_sheets.pdfIn PDF document text
    • https://s3.amazonaws.com/xufujofaleki/didupubinapabe.pdfIn 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_off00011413.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11413 2940 bytes
SHA-256: 72b815926571ed76dcdb15ba0f925f8be737f518649be50e3ea36e0fc125b231
font_01_sfnt_off00011e9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E9F 5428 bytes
SHA-256: 87792bcf365a78fcf134d59af36c1572384a3d94b2d94ecf4bb23e09484af79f
font_02_sfnt_off00013115.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13115 11800 bytes
SHA-256: 7da22999f40d545a97fb7fcdbc8538dcefa99c6cf34c353507bcae7cd8b3e3ae