Malicious PDF — malware analysis report

Static analysis result for SHA-256 de951acd91b8da52…

MALICIOUS

PDF

51.8 KB Created: 2020-07-17 02:53:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-04
MD5: ae424f0ac3bb5f7d60aed57461a16da2 SHA-1: 9242045017d125b50c5e1a2085cb854b25faa3b8 SHA-256: de951acd91b8da523ae014993f57ba88f64e02a39ac43ca3e7b10909e0a5e509
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains multiple heuristics indicating it links to known malicious redirector infrastructure and is part of a link farm designed for SEO manipulation. The primary URL identified, 'https://ttraff.ru/wb?keyword=lector%20de%20pdf%20ultra%20ligero%20', is flagged as malicious. The ML classifier strongly supports the malicious nature of this PDF. No scripts were extracted, and the document body was unreadable, but the URL and heuristic findings are sufficient to determine the malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 6

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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 http://files.eaplab.eu/uploads/1/3/0/7/130740127/2255032.pdf In PDF document text
    • http://files.lexroulor.com/uploads/1/3/2/7/132710776/97aaa103b225.pdfIn PDF document text
    • http://files.ivanbavcevic.com/uploads/1/3/2/6/132696512/7ea1fd4b4.pdfIn PDF document text
    • http://files.mirtecsignage.com/uploads/1/3/0/7/130776001/rerako.pdfIn PDF document text
    • http://files.getsolution.ca/uploads/1/3/0/7/130739222/2f991b.pdfIn PDF document text
    • http://files.jroennau.com/uploads/1/3/1/4/131438423/066416dd88.pdfIn PDF document text
    • http://files.jamiescrew22.org/uploads/1/3/2/8/132815181/libubusozenu.pdfIn PDF document text
    • http://files.wolfetonesboston.com/uploads/1/3/0/9/130969553/bojijeto_fefimopesogod.pdfIn PDF document text
    • http://files.saltysirentradingco.org/uploads/1/3/1/3/131379039/5377148.pdfIn PDF document text
    • https://ttraff.ru/wb?keyword=lector%20de%20pdf%20ultra%20ligero%20PDF link annotation
    • https://ttraff.ru/wb?keyword=lector%20de%20pdf%20ultra%20ligero%20(adobe%20reader%20liteIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://jebopabenudu.files.wordpress.com/2020/06/51523057868.pdfIn PDF document text
    • https://xobodisupoka.files.wordpress.com/2020/07/vakumezum.pdfIn PDF document text
    • https://zubijunemovo.files.wordpress.com/2020/06/vagugevedunowojute.pdfIn PDF document text
    • https://kalateti.files.wordpress.com/2020/07/11872052978.pdfIn PDF document text
    • https://rotanafipiso.files.wordpress.com/2020/07/17080841518.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/0877/0726/files/7444788903.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/80804151078.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/1631/4277/files/taragujubikasidanosa.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/5557/0341/files/36612081055.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/0776/9750/files/situginiba.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/ganisififado.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_off00007ddc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7DDC 5156 bytes
SHA-256: 71cfd3d9c85fbe53409a18baa4fedaab143a3671c23e35f8451209c68d500abb
font_01_sfnt_off00008f86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8F86 15620 bytes
SHA-256: c1ddff3eece3e7c2d42c6f2fede0720c923a3b6538532928b01e1c56960ef8bf