Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8869f534d15e9dd…

MALICIOUS

PDF

73.7 KB Created: 2021-06-11 00:39:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 101b84923ec2aa6cb7e22c062fdc3e8c SHA-1: f87e1f311438bc27eaad6cb66b1412326d4cf86c SHA-256: c8869f534d15e9dd9c5eaf370b3f836950e301132fd3dc8a2660347c62911828
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 0.9995

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://huntic.ru/pbw?utm_term=accounting+principles+kieso+pdf+free+download PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4387417/normal_601d1c81a48a5.pdfIn PDF document text
    • https://kafolegilu.weebly.com/uploads/1/3/2/3/132303068/924529.pdfIn PDF document text
    • https://nuvarimo.weebly.com/uploads/1/3/1/3/131378817/7531575.pdfIn PDF document text
    • https://mabexerezigija.weebly.com/uploads/1/3/5/3/135324341/1138129.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405184/normal_5fd8a26104b98.pdfIn PDF document text
    • https://garisufusomepis.weebly.com/uploads/1/3/0/7/130740000/7441180.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4426828/normal_5fec3ca43c857.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4482849/normal_5fc76dedc2516.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4417325/normal_5fe8233c51eb1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4472213/normal_6059b3ded996c.pdfIn PDF document text
    • https://pakokapixufepu.weebly.com/uploads/1/3/4/6/134659136/bizovugo_ditija_vagoju_dowowebuvibebo.pdfIn PDF document text
    • https://dalenorilesa.weebly.com/uploads/1/3/4/8/134858788/gexovek_panevu_nivomolog_jasib.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388427/normal_60b94ff810e57.pdfIn PDF document text
    • https://rixilokif.weebly.com/uploads/1/3/4/1/134109141/virunuvuwik.pdfIn PDF document text
    • https://sawilemevopano.weebly.com/uploads/1/3/4/5/134577559/maxenejuvabufelusak.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/0108cf1e-0489-461f-988d-b678956b29df/gesegepuzumuwined.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8fee8b24-3060-42d5-929e-90a3a5ad39bc/mauser_98_bayonet_for_sale.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ad900df6-110c-43a6-8adb-d605b78397d8/adobe_premiere_pro_cc_2017_price_in_india.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c9f3702d-4960-47f5-9f86-c97a6969a917/weeds_of_nebraska_and_the_great_plains.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/20ab9a1d-3031-45d6-909b-7d7a0e0e0c50/life_after_high_school_speech.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ccb39855-866f-4895-9ba9-89570d4552e1/information_technology_specialist_1_range_c.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9337ea18-9f17-422f-b842-5c8dcd1f1b08/67040105081.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_off0000df7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF7F 5468 bytes
SHA-256: 15e323e3201dba0b2ede15b21ef3eba67a8f077f5f3e2ffcfb7b754f74c86516
font_01_sfnt_off0000f243.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF243 11200 bytes
SHA-256: 282068b338042cfcdc03fb3c7b3e44b18c426a51adf0547ef82ec472523905ba