Malicious PDF — malware analysis report

Static analysis result for SHA-256 404c7dd0a618c0ba…

MALICIOUS

PDF

39.9 KB Created: 2020-07-31 03:51:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 07e88b18e6cf58a1881fa07109f8a9e2 SHA-1: 8503afdf4d8bcbc87b754fc648ce476e6dc1d4c1 SHA-256: 404c7dd0a618c0ba9a1b001635fc49dd126044afb4dd06185b66b10752ff47e9
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link T1059.001 PowerShell

The PDF contains a large number of embedded links, many pointing to Shopify domains, which are likely part of a link farm designed to obscure the ultimate destination. One critical heuristic identified a link to a known malicious redirector, ttraff.ru, which is used to deliver the final payload. The ML classifier strongly indicated maliciousness. The document body text, though heavily obfuscated, appears to be a lure for a book download, aligning with the link farm technique.

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=basic+economics+thomas+sowell+pdf+download
    • http://files.angelafiori.com/uploads/1/3/1/4/131409090/3511276.pdf
    • http://files.mosaicdownsyndrome.com/uploads/1/3/2/7/132741035/5866938.pdf
    • http://files.moissaniteny.com/uploads/1/3/0/9/130970008/rokomonusufewem.pdf
    • http://files.carolinaspecialtyproducts.com/uploads/1/3/1/0/131070618/2e479.pdf
    • https://cdn.shopify.com/s/files/1/0428/6251/0236/files/94843506505.pdf
    • https://cdn.shopify.com/s/files/1/0434/8346/3832/files/gorijiwavezak.pdf
    • https://cdn.shopify.com/s/files/1/0431/8996/0861/files/4013009862.pdf
    • https://cdn.shopify.com/s/files/1/0434/4800/8866/files/vusorisivis.pdf
    • https://cdn.shopify.com/s/files/1/0432/6667/0745/files/titapogawuv.pdf
    • https://cdn.shopify.com/s/files/1/0431/5453/8658/files/81522337671.pdf
    • https://cdn.shopify.com/s/files/1/0428/2168/1315/files/dixejijuwifunov.pdf
    • https://cdn.shopify.com/s/files/1/0438/1786/1277/files/77088920232.pdf
    • https://cdn.shopify.com/s/files/1/0434/5197/3794/files/fatepun.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/
    • https://cdn.shopify.com/s/files/1/0434/4800/8866/files/vusori

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005d08.bin
0c633c341c82d7bb1bf3eecf56028addda2b1b09b2adbe740f680d5132af4a7e
pdf-font-stream PDF embedded font (sfnt) at offset 0x5D08 5228 bytes
font_01_sfnt_off00006ead.bin
4fcaa2c402c98694f6d32f614c191255022803f07f4f1c21899b333be7f831f3
pdf-font-stream PDF embedded font (sfnt) at offset 0x6EAD 10476 bytes