Malicious PDF — malware analysis report

Static analysis result for SHA-256 99bd837f68bbdc34…

MALICIOUS

PDF

40.0 KB Created: 2020-05-19 15:50:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-24
MD5: d0c9c2908ace48a61cccfd0cf7090856 SHA-1: 651f9dc6896141f2116e5cbaa55cc83342fe21ce SHA-256: 99bd837f68bbdc348106fbf9ce5d2d25e2ddb8f614520a057810c58efcce4af3
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1105 Ingress Tool Transfer

The PDF file contains a large number of embedded external links to various domains, identified by the PDF_SEO_LINK_FARM heuristic. The ML classifier also strongly indicated maliciousness. These links likely serve to direct users to potentially malicious content or to engage in SEO spam tactics. No scripts were extracted, but the sheer volume of external links suggests a content-distribution or redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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://narpestakpak.com/uploads/1/3/0/8/130873914/130873914.html#o+evangelho+de+maria+madalena+completo+pdf PDF link annotation
    • http://aerialadvantagepoint.com/uploads/1/3/0/6/130639547/1911487.pdfIn PDF document text
    • http://purelifelvpropertiescom.com/uploads/1/3/0/8/130874364/sixedam_jefulemel.pdfIn PDF document text
    • http://nutribreast.com/uploads/1/3/0/5/130543333/jafopopubaxumekul.pdfIn PDF document text
    • http://twinkletoespetcare.com/uploads/1/3/0/6/130621533/kekunifafu.pdfIn PDF document text
    • http://tinokunda.org/uploads/1/3/1/3/131383975/mejamax.pdfIn PDF document text
    • http://outdoorsactivewell.org/uploads/1/3/0/7/130739371/9696890.pdfIn PDF document text
    • http://ashamandela.com/uploads/1/3/0/8/130814784/608db39f21ab22.pdfIn PDF document text
    • http://suitlandhsfeasibilitystudy.com/uploads/1/3/1/3/131379671/0aaa617ed2a.pdfIn PDF document text
    • http://winandchocolate.com/uploads/1/3/1/3/131382590/379817.pdfIn PDF document text
    • http://luliudesign.com/uploads/1/3/0/6/130620690/fatuxidiramizase.pdfIn PDF document text
    • http://fastestwaytoloseweightsystem.com/uploads/1/3/0/6/130621114/jufotutewit_mazeso.pdfIn PDF document text
    • http://dauphinkom.ca/uploads/1/3/1/4/131437980/juzobusakodoxa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006c90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6C90 12596 bytes
SHA-256: e99930c23d639f8edf911c7c35647fe82c365dd725e5f1bf278206726ad36fe0