Malicious PDF — malware analysis report

Static analysis result for SHA-256 725286886b6c5d11…

MALICIOUS

PDF

41.1 KB Created: 2020-08-30 19:36:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: a29e3bbf69d065d086698c4013544f55 SHA-1: c62d5466dc51a5f212e1b4aa172e1984638d27d1 SHA-256: 725286886b6c5d11da952914fd758d6fabf3e89056e47841b3dc4707306da6d2
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded links, many of which point to SEO-optimized PDF files, a technique often used to obscure malicious redirects. One of the primary links directs to a known malicious redirector. The ML classifier also strongly indicated maliciousness. No scripts were extracted, but the structure and embedded links suggest a phishing or redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • 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.ru/wix?keyword=ejercicios+de+mecanografia+para+impr
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/469aea_fe30a3a35cc447338cdf53de536733b1.pdf
    • https://static.usrfiles.com/ugd/eaf48f_e0ce23b1d08d43bdadf5ddd74c8c0aef.pdf
    • https://static.usrfiles.com/ugd/b8c837_6b61e6cd388a42f48e0b2d3385a06b1d.pdf
    • https://static.usrfiles.com/ugd/696117_3cbd1b4d2f3c4da294405d6fcdb8ea77.pdf
    • https://static.usrfiles.com/ugd/625844_62b0d4583a494a1ab563f16e133d4640.pdf
    • https://static.usrfiles.com/ugd/b8c837_4ce93d7e56684d80976aec5ef8e902b1.pdf
    • https://static.usrfiles.com/ugd/fd3290_fc802c1a48c74af591768e76dbbdb1c3.pdf
    • https://static.usrfiles.com/ugd/b8c837_2dc5fa4aef0642abb8432000f11f9378.pdf
    • https://cdn.shopify.com/s/files/1/0452/4628/3937/files/bilirrubina_directa_alta.pdf
    • https://cdn.shopify.com/s/files/1/0432/4930/3720/files/9129371314.pdf
    • https://cdn.shopify.com/s/files/1/0432/2826/6654/files/89566168312.pdf
    • https://cdn.shopify.com/s/files/1/0431/6109/2245/files/11423104836.pdf
    • https://cdn.shopify.com/s/files/1/0429/6821/9799/files/sujuweverubanupo.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000060b1.bin
b6679b18357ebe57eb5a255d6eed03d0049b77cf769f12fd1e2b06c17e3a0f03
pdf-font-stream PDF embedded font (sfnt) at offset 0x60B1 5476 bytes
font_01_sfnt_off0000733e.bin
6908e169a0de1e21e250090385098af13e8b1853fff23b62c9c657d03e04b84a
pdf-font-stream PDF embedded font (sfnt) at offset 0x733E 10744 bytes