Malicious PDF — malware analysis report

Static analysis result for SHA-256 5cfb1b5b6f819185…

MALICIOUS

PDF

79.2 KB Created: 2021-04-07 22:36:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 4744ce675d01fc3c2155ffcff79e3732 SHA-1: dcc00e3bf54627b2fea5b285d13cf219d5c0aca0 SHA-256: 5cfb1b5b6f819185ce681c57704fc807d63621ae8bc68fa6fd53a6c25dd763d8
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 0.9997

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
  • 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://maypoin.ru/strik?utm_term=free+thanksgiving+math+worksheets+3rd+grade PDF link annotation
    • https://cdn.sqhk.co/samofetob/nGD2ICE/86146715151.pdfIn PDF document text
    • https://cdn.sqhk.co/gewewoturila/nkjiLgj/jogo_super_slime_simulator_online.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4473064/normal_60658d9fabb16.pdfIn PDF document text
    • http://qwertyujg.xyz/6147732309410axv.pdfIn PDF document text
    • http://astropsychology.site/tixasegoft11jp.pdfIn PDF document text
    • http://lami-lashes.site/sekoragazixufetqpt.pdfIn PDF document text
    • http://polibesafonujof.iblogger.org/dawoodi_bohra_calendar_1439.pdfIn PDF document text
    • http://googsnat.space/sevanebasdtpxs.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449405/normal_6059646ef0562.pdfIn PDF document text
    • https://cdn.sqhk.co/sipobufiw/bugjioN/35504963913.pdfIn PDF document text
    • https://cdn.sqhk.co/wopeporamo/Vtdhgif/xikolararezumadadikidefo.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4471682/normal_5ff0a61540ec8.pdfIn PDF document text
    • http://afracheat7.xyz/vutosototogzthse.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://44f68060-d5e3-4d58-b4e7-e3760392f352.filesusr.com/ugd/49488e_5c30c6ec379b497ca891737117a85bbd.pdf?index=trueIn PDF document text
    • https://ee6bc897-aa08-459d-b6e6-b1b1d69fcba1.filesusr.com/ugd/7ba596_9967624732d448a9ae284bc71b254bf4.pdf?index=trueIn PDF document text
    • https://c33c3ce4-fa2f-4f19-9477-7a801b41b29e.filesusr.com/ugd/ebbcbd_59137de20edd489aadff29c50cc19bd6.pdf?index=trueIn PDF document text
    • https://4253c66a-660d-4c83-b31d-f715833d547b.filesusr.com/ugd/d9e9a0_143d65b10d8f447884921ce57e6ccef2.pdf?index=trueIn PDF document text
    • https://57fc24c6-ba7c-430a-bdae-05304608b610.filesusr.com/ugd/bc9c68_3635d8c128974074956b83a3523c7943.pdf?index=trueIn PDF document text
    • https://82f7a8bd-e2a3-46ec-bdf8-dd4727f017fb.filesusr.com/ugd/a90de3_d11435080abb4f9382c04766e4c03be6.pdf?index=trueIn PDF document text
    • https://933527c5-e005-4225-a3aa-05fee46c7696.filesusr.com/ugd/b51dd5_82c5b14515004e838a72d76f96147a92.pdf?index=trueIn PDF document text
    • http://jotozig.rf.gd/domiluki.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_off0000f76c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF76C 5540 bytes
SHA-256: 821723053889297de43698f2942599fe02d1e7636dfe3d859b5eafeedb9e9f3b
font_01_sfnt_off00010a32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A32 10324 bytes
SHA-256: 1f70dfec712d9f20c7972dc338e9d6b8514ae4a542dfafd2a814c155d3b11d4d