Malicious PDF — malware analysis report

Static analysis result for SHA-256 4be9dce86d467251…

MALICIOUS

PDF

45.2 KB Created: 2020-03-23 01:39:37 +02:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6)
MD5: 23f84c6620479d49915db9c646b9ca06 SHA-1: 2d6cba5f23ec6f8f09568260684de16fc940356d SHA-256: 4be9dce86d4672511e78b89e7fdec71796ce0c57116745b0f5786d1e2e7f4b00
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded URLs pointing to various domains, indicating a link farm or SEO spamming operation. The ML classifier strongly suggests maliciousness. The primary attack pattern involves directing users to a multitude of external PDF files, likely to distribute further malicious content or engage in SEO manipulation. No scripts were extracted, limiting the analysis of direct payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • 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://michaelwellsart.com/uploads/1/3/0/5/130588294/130588294.html#puntaje+minimo+para+administracion+de+negocios+internacionales+unmsm
    • http://www.byyoursidels.com/uploads/1/3/0/7/130740450/devifupikifozug.pdf
    • http://delgadillonews.com/uploads/1/3/0/3/130323213/80794d4a5.pdf
    • http://mta-sts.mx.bodycareclinicriverside.com/uploads/1/3/0/6/130604014/9271716.pdf
    • http://kissolutions.co.nz/uploads/1/3/0/7/130738790/062a34b.pdf
    • http://www.yeah-cindi-di.com/uploads/1/3/0/9/130969655/satalirubunapelitiwe.pdf
    • http://artbydelayne.com/uploads/1/3/0/3/130313178/wizetamaba-fevakikazulesu.pdf
    • http://www.sanchezstreaming.sanchezcomunications.com/uploads/1/3/0/4/130435755/2380632.pdf
    • http://thefirmm.com/uploads/1/3/0/7/130775878/8027132.pdf
    • http://www.smartmobilityusa.com/uploads/1/3/0/2/130270987/xedawafibulolame.pdf
    • http://www.therepurposedlife.net/uploads/1/3/0/7/130739655/7104704.pdf
    • http://siouxcitypropainting.com/uploads/1/3/0/4/130483216/52dce85.pdf
    • http://olykraut.net/uploads/1/3/0/4/130436222/sidodemewupemi-nujumudupufe.pdf
    • http://msftftden2016.com/uploads/1/3/0/7/130739895/sasulosiwado.pdf
    • http://travelfeet.co.nz/uploads/1/3/0/6/130620929/10cd508d8.pdf
    • http://remingtonagency.net/uploads/1/3/0/2/130272340/lopejaj.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/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006fdc.bin
0cf03d3c1e92f79a63f657d0680fdec4a71171131bf50ba51298caaec978a1cc
pdf-font-stream PDF embedded font (sfnt) at offset 0x6FDC 8864 bytes
font_01_sfnt_off00008f64.bin
40a403f8312ff9c93041e514e965a4d57d797ba541f1da729710ef172887bfc2
pdf-font-stream PDF embedded font (sfnt) at offset 0x8F64 16060 bytes