Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9663aa5b97b348e…

MALICIOUS

PDF

42.8 KB Created: 2020-08-19 06:38:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 28c2d3644d5360b26e5a83133398500a SHA-1: 185389d2d1b94028e9b3fac517b8003e441f065f SHA-256: a9663aa5b97b348e5d5e4d97e4d353d8ccbd80383cc4475247df83f0ae0be9ce
154 Risk Score

Malware Insights

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

The PDF file contains a significant number of embedded links, many of which are part of a link farm. One prominent URL, 'https://ttraff.ru/pify?keyword=propiedades+del+salvado+de+trigo+pdf', is identified as a malicious redirector. The ML classifier also strongly indicated maliciousness. The document body itself is largely unreadable binary data, but it does contain the suspicious URL and several other PDF links hosted on various domains, suggesting a coordinated effort to distribute malicious 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=propiedades+del+salvado+de+trigo+pdf
    • http://nuxavuni.ibelongamen.com/uploads/1/3/0/7/130776617/ragoneguxe-newuzen-fujewumamonavaw-xegased.pdf
    • http://biloji.suvituominen.com/uploads/1/3/0/7/130776407/nonukil_vuregamopom.pdf
    • http://files.mapleafdals.com/uploads/1/3/1/8/131871583/webetanifixem-nezema.pdf
    • https://cdn.shopify.com/s/files/1/0435/4880/3227/files/worksheets_for_kindergarten.pdf
    • https://cdn.shopify.com/s/files/1/0432/5005/7373/files/batefawuposalafudajuxax.pdf
    • https://cdn.shopify.com/s/files/1/0438/1566/5824/files/remerejeziraki.pdf
    • https://cdn.shopify.com/s/files/1/0437/4921/2311/files/cvc_words_activities_for_kindergarten.pdf
    • https://cdn.shopify.com/s/files/1/0432/6457/3593/files/56845386304.pdf
    • https://cdn.shopify.com/s/files/1/0433/8886/2622/files/zanikelokuzunanuxoxivid.pdf
    • https://cdn.shopify.com/s/files/1/0444/6614/3399/files/zunufomesig.pdf
    • https://cdn.shopify.com/s/files/1/0434/0757/3149/files/cobb_bbq_recipe_book.pdf
    • https://cdn.shopify.com/s/files/1/0430/1615/9381/files/vilebarik.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/16711599054.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/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006054.bin
dfd2720993010e09c1d41d3a75a8d87b490c25d26e49fdd6e1b9fa0d65ee7276
pdf-font-stream PDF embedded font (sfnt) at offset 0x6054 5268 bytes
font_01_sfnt_off00007255.bin
779bed2639dfb8e1ee1150a55b7c515a91d125a59abc9f7454b3c498d5925582
pdf-font-stream PDF embedded font (sfnt) at offset 0x7255 13772 bytes