Malicious PDF — malware analysis report

Static analysis result for SHA-256 c41d2a26c0a4862f…

MALICIOUS

PDF

67.8 KB Created: 2021-05-27 10:21:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 513967f70e8ba5bef27d2b6c88b20cfe SHA-1: 5603e985b103e841c13f9ed4ff65bc83c62f85a2 SHA-256: c41d2a26c0a4862f665f9d5b5661e3857ebb975a80129321f626865c7540dc98
226 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. It uses a password-protected-archive lure. 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 0.9998

Heuristics 7

  • 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.
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://seumenha.ru/strik?utm_term=como+falar+corretamente+reinaldo+polito+pdf+download+gratis PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4377936/normal_60537a22d634a.pdfIn PDF document text
    • https://jojobejuw.weebly.com/uploads/1/3/2/8/132815094/5484127.pdfIn PDF document text
    • https://dexugagemer.weebly.com/uploads/1/3/4/7/134715037/wesudetimoxunesu.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4466408/normal_60038e27e249f.pdfIn PDF document text
    • https://vajemedodumuni.weebly.com/uploads/1/3/4/3/134351385/zerin.pdfIn PDF document text
    • https://dupemokuko.weebly.com/uploads/1/3/4/7/134759865/jubitasiri.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465015/normal_6011e4139de15.pdfIn PDF document text
    • https://retariluwefise.weebly.com/uploads/1/3/4/8/134858211/popovabafopu.pdfIn PDF document text
    • https://rusakubasarozu.weebly.com/uploads/1/3/4/2/134266120/radurik.pdfIn PDF document text
    • https://kezugavamatuwe.weebly.com/uploads/1/3/5/3/135347357/japaxabuvur.pdfIn PDF document text
    • https://sawilemevopano.weebly.com/uploads/1/3/4/5/134577559/af9e0b76c9b731d.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4495685/normal_6009a29293caa.pdfIn PDF document text
    • https://mizefowoxeze.weebly.com/uploads/1/3/4/4/134485365/pogumikij.pdfIn PDF document text
    • https://jugoneworo.weebly.com/uploads/1/3/4/3/134307205/pekesiko_balamadodoxezo_zixidujoto.pdfIn PDF document text
    • https://faromemexe.weebly.com/uploads/1/3/5/3/135399009/787c57.pdfIn PDF document text
    • https://nafogoke.weebly.com/uploads/1/3/4/7/134776139/4196399.pdfIn PDF document text
    • https://ragurinibobuma.weebly.com/uploads/1/3/3/9/133986244/6be12105f46.pdfIn PDF document text
    • https://jivimukik.weebly.com/uploads/1/3/0/7/130775904/4550d9a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4475572/normal_5fd0f0bd7a620.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_off0000c834.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC834 5472 bytes
SHA-256: 4d498c311442eac67af0cfbcfa6fdc761884ad90d26ab584e131341bb06b8c54
font_01_sfnt_off0000daca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDACA 11644 bytes
SHA-256: 42acce9f96680491bded1693c015ac4232525b1b07546f76c614449cea9be38e