Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1bd5f734a6ce444…

MALICIOUS

PDF

68.8 KB Created: 2021-03-08 20:46:35 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: ceb54855f91b6afe672e3420ecb3def8 SHA-1: a651aefe7e98d6802f15d68a1647342c344bd212 SHA-256: b1bd5f734a6ce444b76b509dfcdfe337e3707cfb7d433f7564751d54ce6c7e3c
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting services, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent. The embedded URL 'https://jacksth.ru/strik?utm_term=how+to+reset+an+ellipsis+8+tablet' is likely part of the malicious redirection chain.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://jacksth.ru/strik?utm_term=how+to+reset+an+ellipsis+8+tablet PDF link annotation
    • https://zejenabo.weebly.com/uploads/1/3/0/9/130969472/tepali_nukufijujufi.pdfIn PDF document text
    • http://jirusulixozome.scienceontheweb.net/zuvubomu.pdfIn PDF document text
    • https://cdn.sqhk.co/lagazowasobo/NaHgchd/kukojazedevedub.pdfIn PDF document text
    • https://cdn.sqhk.co/rabawula/KPDgihb/fetofuludojanetawegem.pdfIn PDF document text
    • https://ruzudagozigiwis.weebly.com/uploads/1/3/5/3/135394236/zokubomavarutakit.pdfIn PDF document text
    • https://nolaxefipox.weebly.com/uploads/1/3/4/7/134740184/venelekukuj.pdfIn PDF document text
    • http://kilijosizujowo.medianewsonline.com/why_do_i_ejaculate_different_amounts.pdfIn PDF document text
    • https://tuwoganerolet.weebly.com/uploads/1/3/4/6/134631505/426913.pdfIn PDF document text
    • https://cdn.sqhk.co/pujazojiwixi/EpaHidy/human_resource_management_online_course_philippines.pdfIn PDF document text
    • https://cdn.sqhk.co/sivadapexiri/geljMXo/41461757239.pdfIn PDF document text
    • http://kumululurug.scienceontheweb.net/pafor.pdfIn PDF document text
    • http://fegokodelaxen.scienceontheweb.net/86035644082.pdfIn PDF document text
    • https://cdn.sqhk.co/jigavozef/GDJkEhh/89919712528.pdfIn PDF document text
    • https://mawatewif.weebly.com/uploads/1/3/0/9/130969671/401703a58.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://sinipuxi.epizy.com/gamutur.pdfIn PDF document text
    • http://nepejalaziba.rf.gd/netflix_android_tv_box_apk_2019.pdfIn PDF document text
    • http://zusaxadixuxot.myartsonline.com/40272343706.pdfIn PDF document text
    • http://popofisofol.myartsonline.com/nosezofepexokamakurir.pdfIn PDF document text
    • https://f4dd034e-00c7-465c-b850-fb2d75accad5.filesusr.com/ugd/769f78_bd18be9e50904d449351ab16d99179cf.pdf?index=trueIn PDF document text
    • https://089130c0-62ae-4bf1-a93c-656440fe8451.filesusr.com/ugd/738632_c7da06f038494911b51d7c6ea6d83e72.pdf?index=trueIn PDF document text
    • https://6fd4412c-3e6e-4f21-a9af-8137ffc6c0d9.filesusr.com/ugd/03469c_576fdd53b9014325ae43b1de1b44c978.pdf?index=trueIn PDF document text
    • https://5057b38b-f250-4925-a5fd-2dbc054a2c1f.filesusr.com/ugd/25ee37_7e4ff568eeec4726afb61169860a1290.pdf?index=trueIn 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_off0000d0fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0FC 5200 bytes
SHA-256: a6137e48f10bb65fbb1f7e79b187250f9a16cb064866c30001fd1e32b4f93f70
font_01_sfnt_off0000e2c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2C1 10348 bytes
SHA-256: 6cdc2bd487a96b202c60f288f476a9dfd1f7df12af9ae5804e787a11d9466cd0