Malicious PDF — malware analysis report

Static analysis result for SHA-256 c505b7cf379ef46d…

MALICIOUS

PDF

68.1 KB Created: 2021-01-18 08:16:05 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1b212425bff4eb559d1fe029148fbac2 SHA-1: ef59e3168307c8423a279bf2366af369638c5db2 SHA-256: c505b7cf379ef46d464d535a4b24d30e4ff4bf3e1dbdd10551f374572491dd18
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, indicating a link farm or phishing attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded URIs point towards an attempt to redirect users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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 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://traffking.ru/123?utm_term=bokutachi+ga+yarimashita+dramacool
    • https://cdn-cms.f-static.net/uploads/4412894/normal_5fc13c456fc9b.pdf
    • https://tamagokevalagir.weebly.com/uploads/1/3/0/7/130776783/rapotikezu_fisogivix_mutiretebiga_newegufikewekis.pdf
    • https://nubeboganiroj.weebly.com/uploads/1/3/1/3/131384383/6d90f.pdf
    • https://site-1176700.mozfiles.com/files/1176700/suvusawun.pdf
    • http://xefakuwejufo.iblogger.org/mulerosalila.pdf
    • https://guxolufesa.weebly.com/uploads/1/3/4/4/134468064/69e21183daeb10.pdf
    • https://juzopuxenepin.weebly.com/uploads/1/3/5/3/135383483/zigidafaroxu.pdf
    • https://nufusuninad.weebly.com/uploads/1/3/4/6/134609023/aa5b588.pdf
    • https://kigefewapese.weebly.com/uploads/1/3/4/5/134528385/2437659.pdf
    • https://static.s123-cdn-static.com/uploads/4425723/normal_5fdf2dafa6b5e.pdf
    • https://site-1175130.mozfiles.com/files/1175130/pure_flix_subscription_prices.pdf
    • https://puxefulido.weebly.com/uploads/1/3/1/3/131383426/eb76c22.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://jotikovan.rf.gd/browallia_new_thai_font.pdf
    • http://vibesegajepo.epizy.com/52852094425.pdf
    • https://s3.amazonaws.com/tomamujuf/google_sheets_query_offset.pdf
    • https://s3.amazonaws.com/tadovu/barras_paralelas_para_rehabilitacion.pdf
    • http://pitupeg.epizy.com/wenakofapo.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bf98.bin
28879cd71a89864b0707ae30a34579c61ed871c783808f9b05ac9ecb108b92e3
pdf-font-stream PDF embedded font (sfnt) at offset 0xBF98 4136 bytes
font_01_sfnt_off0000ce1d.bin
6a9ba69e0a51a6fd8cd434257e52810baa35a3cd68943956a2e6fe855188bf5d
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE1D 5568 bytes
font_02_sfnt_off0000e0ee.bin
2bee90efdf32552fda60b2a63e4718e4bb4e4e1e1b4d4be63b87d60820143ef0
pdf-font-stream PDF embedded font (sfnt) at offset 0xE0EE 10016 bytes