Malicious PDF — malware analysis report

Static analysis result for SHA-256 78b1a824b36f1b14…

MALICIOUS

PDF

62.6 KB Created: 2020-08-15 06:07:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0bb4241985dc7024a98b4248a1f1a9be SHA-1: 3172e727c5ca0c7677913b098224a11d5405150b SHA-256: 78b1a824b36f1b14f0dcf9ab702d893a5fd68351f93f884102a1701bb2421f85
154 Risk Score

Malware Insights

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

The PDF contains a heuristic firing for linking to known malicious redirector infrastructure, specifically pointing to 'https://ttraff.ru/pify?keyword=equal+arm+balance+worksheet'. Additionally, the document exhibits characteristics of a link farm, embedding numerous external PDF links, many of which are hosted on Shopify. The ML classifier strongly flagged this PDF as malicious, supporting the conclusion that it is designed to redirect users to harmful content.

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/pify?keyword=equal+arm+balance+worksheet
    • http://files.internationaldmd.com/uploads/1/3/1/4/131437453/a96cd01fd22d86.pdf
    • http://files.vterryscience.com/uploads/1/3/1/3/131380841/8410fee2806a3.pdf
    • http://files.writinginkc.com/uploads/1/3/1/3/131398145/zajufuxenule-rawetonobe-kasakuz.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0446/9365/1610/files/voxik.pdf
    • https://cdn.shopify.com/s/files/1/0435/2973/2248/files/kigugi.pdf
    • https://cdn.shopify.com/s/files/1/0435/4329/8207/files/8836342146.pdf
    • https://cdn.shopify.com/s/files/1/0430/6858/8194/files/audio_books_in_marathi_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0432/8452/9310/files/mepenekeseva.pdf
    • https://cdn.shopify.com/s/files/1/0432/9318/0070/files/clicks_catalogue_august_2020.pdf
    • https://cdn.shopify.com/s/files/1/0429/7365/9290/files/26233834174.pdf
    • https://cdn.shopify.com/s/files/1/0435/8488/0798/files/48390276139.pdf
    • https://cdn.shopify.com/s/files/1/0435/8832/1437/files/43257055435.pdf
    • https://cdn.shopify.com/s/files/1/0435/4100/4439/files/pexemegekevisi.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_off0000b819.bin
38ad9a0fb50745cd57de7027e0f6052504bd0ed22ecd5e947786b7365032f4e8
pdf-font-stream PDF embedded font (sfnt) at offset 0xB819 5416 bytes
font_01_sfnt_off0000ca67.bin
8dc34ea8aa4197878b4b1e5d995efd65541564495c536016a18fa9ab5e72e4f3
pdf-font-stream PDF embedded font (sfnt) at offset 0xCA67 10364 bytes