Malicious PDF — malware analysis report

Static analysis result for SHA-256 655319d25088b435…

MALICIOUS

PDF

51.3 KB Created: 2020-08-24 15:27:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 4ad4cb0ebe652b26cb5b55fd8080d3fd SHA-1: c14cd53607a8a0db73373969c2bba5876152b129 SHA-256: 655319d25088b435847bcdc4fe83962275a45101394f5c1b5377e73c9e6445eb
154 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.com, disguised as a free legal calculation book. The document also features a link farm of numerous PDFs hosted on Shopify, many of which are benign but serve to obscure the malicious intent. The ML classifier strongly indicated maliciousness, supporting the conclusion that this PDF is designed for malicious redirection.

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.com/pify?keyword=livro+calculos+trabalhistas++gratis
    • http://files.artbyamandahorn.com/uploads/1/3/1/0/131070539/rifipena-dirukizi-bajubabitadoj.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://cdn.shopify.com/s/files/1/0432/9478/5694/files/91920185856.pdf
    • https://cdn.shopify.com/s/files/1/0440/6870/0310/files/vezurazipune.pdf
    • https://cdn.shopify.com/s/files/1/0434/2156/5078/files/taxigazufoziduxuxurezep.pdf
    • https://cdn.shopify.com/s/files/1/0435/8003/1137/files/general_characters_of_aves.pdf
    • https://cdn.shopify.com/s/files/1/0431/7567/4024/files/wupudurutufegevu.pdf
    • https://cdn.shopify.com/s/files/1/0443/1849/0780/files/pubusezepojegetozojepam.pdf
    • https://cdn.shopify.com/s/files/1/0437/8460/1752/files/75447655051.pdf
    • https://cdn.shopify.com/s/files/1/0431/7678/8117/files/31610686364.pdf
    • https://cdn.shopify.com/s/files/1/0428/2544/9628/files/23519713627.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000074d0.bin
bf2aff6c4814a0ae08b1d548a9a2008f19b0f3a622f1e8df24f262983ebe77be
pdf-font-stream PDF embedded font (sfnt) at offset 0x74D0 4860 bytes
font_01_sfnt_off00008566.bin
eead86dd1fce19fcedcdbd031ee1d9cba15d09fbe2e803d5967f510d60ad507a
pdf-font-stream PDF embedded font (sfnt) at offset 0x8566 14608 bytes
font_02_sfnt_off0000b0de.bin
d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378
pdf-font-stream PDF embedded font (sfnt) at offset 0xB0DE 4324 bytes