Malicious PDF — malware analysis report

Static analysis result for SHA-256 4dc63609ef6388f3…

MALICIOUS

PDF

38.7 KB Created: 2020-06-17 18:00:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-08-10
MD5: a6ce5765bff91b101418880c590b2232 SHA-1: 91fe09e776484d98b8279b9ddcc289841422fd56 SHA-256: 4dc63609ef6388f311bc8869c929f555a1ebe852e0f182b155356eb4ab2e9eca
96 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, a technique commonly used for SEO manipulation or to distribute further malicious content. The ML classifier strongly indicated maliciousness. The document body itself is heavily obfuscated but contains references to the URLs, reinforcing the link farm attack pattern.

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://ayambetutu-mbokluh.com/uploads/1/3/0/7/130775084/130775084.html#6550+tube+datasheet PDF link annotation
    • http://brantak.com/uploads/1/3/1/3/131381240/lufekivogi.pdfIn PDF document text
    • http://vaquitaporpoiselisticle.com/uploads/1/3/0/5/130551349/xadaxokovudogenesul.pdfIn PDF document text
    • http://cyber-edchristianschool.com/uploads/1/3/1/4/131407194/3774949.pdfIn PDF document text
    • http://webdisk.blackandpetrichor.com/uploads/1/3/0/6/130640006/vobodaf-kokamofupasov-rusobobom.pdfIn PDF document text
    • http://cpanel.foresightskiguides.org/uploads/1/3/0/3/130313056/fetutofapetug.pdfIn PDF document text
    • http://mx.thewindhorsecenter.com/uploads/1/3/0/6/130620628/8007956.pdfIn PDF document text
    • http://pluggednetworks.co/uploads/1/3/1/3/131383777/d6245e09936f92.pdfIn PDF document text
    • http://mail.dolphinsinternationalschool.sch.ug/uploads/1/3/0/3/130323556/roneluwepus.pdfIn PDF document text
    • http://brittanycollinge.com/uploads/1/3/0/2/130291355/robarojodolapixi.pdfIn PDF document text
    • http://host161.carmichaelnl.com/uploads/1/3/0/7/130775258/d5088e8.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005bc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5BC4 4868 bytes
SHA-256: 2809c436c1ab7127a21e558a47e424a8a64ce553c59ee149a7afdc5d9d6cf02d
font_01_sfnt_off00006c47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6C47 10740 bytes
SHA-256: f21e0e6986c10c057b3e79ab08a4b73b02a8d4eb520332e3d5b0dd29e7b57272