Malicious PDF — malware analysis report

Static analysis result for SHA-256 2a8ac5453c934a87…

MALICIOUS

PDF

47.9 KB Created: 2020-07-07 12:16:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-15
MD5: de8f2cd8a1279af50734660cecb2e41a SHA-1: a4273c47ae49239868346ec70a89d48d00108be6 SHA-256: 2a8ac5453c934a8722b56ec654f4652584c6443c0d24084ddd2c5f1d13994473
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a large number of embedded links, many of which point to domains associated with link farms and redirectors, indicating a phishing or malicious content distribution attempt. The ML classifier strongly flagged this PDF as malicious. The document body, though partially obfuscated, contains keywords related to dental procedures and URLs, reinforcing the lure.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • 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://ttraff.com/wb?keyword=protesis%20total%20dental%20pasos%20pdf#protesis+total+dental+pasos+pdf In PDF document text
    • http://files.squareonegoodsco.com/uploads/1/3/2/8/132815154/tasawaz.pdfIn PDF document text
    • http://files.merarifernandez.com/uploads/1/3/1/4/131407165/6839308.pdfIn PDF document text
    • http://files.southlandfamilyclub.com/uploads/1/3/1/3/131379371/e862cb.pdfIn PDF document text
    • http://files.projectufo.org/uploads/1/3/0/7/130739381/4877757.pdfIn PDF document text
    • http://files.essenceofbeautydublin.com/uploads/1/3/1/6/131637057/9362341.pdfIn PDF document text
    • http://files.minilivestock.com/uploads/1/3/2/7/132740415/38a223c.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://borakav.files.wordpress.com/2020/06/82625290506.pdfIn PDF document text
    • https://sagakav.files.wordpress.com/2020/07/tixurot.pdfIn PDF document text
    • https://dekidox.files.wordpress.com/2020/06/25201261190.pdfIn PDF document text
    • https://kumitewefa.files.wordpress.com/2020/06/12485309396.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_off00007cba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7CBA 4824 bytes
SHA-256: b128d2fd14895477b3186d188799a367dcffe4a0523d40d6fe6bc487004251cb
font_01_sfnt_off00008d1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8D1C 12112 bytes
SHA-256: 0aab5ca7c5086f40c610b9f6472f962264c6229bd645240005ec30efd41694c5