Malicious PDF — malware analysis report

Static analysis result for SHA-256 a983c1d552b8fc55…

MALICIOUS

PDF

72.9 KB Created: 2021-06-11 02:19:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 1f4421f17192c1cc22458317562550fd SHA-1: c38ba31091ab4d6beb840d369cbaeb89c628e6bb SHA-256: a983c1d552b8fc557f2c75595d617e9a5d4a19287cf46555983fdd5220440d35
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://krisoc.ru/pbw?utm_term=wps+wpa+tester+premium+mod+apk PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4467287/normal_5ffaced8b0f0b.pdfIn PDF document text
    • https://xumodaniteged.weebly.com/uploads/1/3/4/4/134480563/xelafezituj_ratow_silowepi.pdfIn PDF document text
    • https://mufuxavezefajox.weebly.com/uploads/1/3/4/4/134497947/ef9eed6f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4456114/normal_603047c8e911d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424024/normal_6023d0b9b6514.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476946/normal_60444ad1f3e17.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4464720/normal_606aa67cd4039.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4383138/normal_603ec6da9ca9b.pdfIn PDF document text
    • https://pamopalosi.weebly.com/uploads/1/3/4/8/134857187/8416915.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4500447/normal_60584a65132cb.pdfIn PDF document text
    • https://lanulizuxuja.weebly.com/uploads/1/3/4/6/134658029/aff129b0bfe48b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415070/normal_6010d081703a7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454544/normal_5fe90ff5aaf53.pdfIn PDF document text
    • https://lidonamu.weebly.com/uploads/1/3/4/7/134722791/6800270.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4377125/normal_60106592dec83.pdfIn PDF document text
    • https://fofebaxokawapo.weebly.com/uploads/1/3/7/4/137499404/98b95c578449.pdfIn PDF document text
    • https://taxajefikudo.weebly.com/uploads/1/3/4/7/134765143/levijatex-besomezifu-sidifekadisib-wibusapabe.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://fosirodovo.pbworks.com/w/file/fetch/144602070/sims_4_expansion_download_mac.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4763eca4-714a-436c-9dbb-f0a0601a513c/how_to_start_electronic_repair_shop_waupaca.pdfIn PDF document text
    • http://nagomax.pbworks.com/f/81235410830.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2fde5a5e-b9a5-4030-8e49-afd5a50aed5e/duguxalulagiradux.pdfIn PDF document text
    • http://jowenoxo.pbworks.com/f/41141240252.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7f43c3a1-2316-41fd-8a1c-e2e45db6e6e8/how_to_cook_rice_in_aroma_professional.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000de79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE79 5244 bytes
SHA-256: 802c5de97d5d125e80e7151f488c4f13ca35c4c9c930cebba58a88c9f47b3971
font_01_sfnt_off0000f04e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF04E 10540 bytes
SHA-256: f5fd6f75e922ef95424b7cdba41c50fd50abe05807096f9eeedf90b324619649