Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c8538341d0cff4f…

MALICIOUS

PDF

43.1 KB Created: 2020-08-08 09:24:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 433e8e27e6fc97203f85fc0a4b3f18b9 SHA-1: ac4ce1839a901b9bdca0a79f10041dce29becded SHA-256: 0c8538341d0cff4fc0d0e8ccd8e15072b76f0941a6e8de342f78d66d0aa2f032
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many of which point to benign Shopify domains, but one critical link directs to a known malicious redirector. The ML classifier also strongly flagged this PDF as malicious. The primary attack pattern appears to be a link farm designed to redirect users to malicious infrastructure.

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=klasifikasi+acetobacter+xylinum+pdf
    • http://xakoxiv.swtradingcompany.com/uploads/1/3/1/3/131398455/7067776.pdf
    • http://files.drsalessystem.com/uploads/1/3/0/7/130775921/visim-podadirapewus-xabumexun.pdf
    • http://files.tcrinnovations.com/uploads/1/3/1/3/131380299/2492604.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0432/1991/0820/files/82832855017.pdf
    • https://cdn.shopify.com/s/files/1/0433/8368/5274/files/95866764116.pdf
    • https://cdn.shopify.com/s/files/1/0431/0581/2633/files/jinma_tractor_parts.pdf
    • https://cdn.shopify.com/s/files/1/0433/0363/3051/files/gabowezavurazuremu.pdf
    • https://cdn.shopify.com/s/files/1/0434/3450/8454/files/principios_del_materialismo_dialectico.pdf
    • https://cdn.shopify.com/s/files/1/0431/8566/8255/files/ethiopian_river_basins.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/magizokoluredofet.pdf
    • https://cdn.shopify.com/s/files/1/0431/4578/9606/files/root_cause_analysis_handbook_free.pdf
    • https://cdn.shopify.com/s/files/1/0433/8909/1998/files/pokokifatowujaxuxotizer.pdf
    • https://cdn.shopify.com/s/files/1/0428/6103/5686/files/absorption_costing_and_variable_costing.pdf
    • https://cdn.shopify.com/s/files/1/0432/3105/1943/files/wipemenet.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_off00006a61.bin
95d4fca79e2f786b1e31525b66b334630b142f881e7b733a11ef5935ba157774
pdf-font-stream PDF embedded font (sfnt) at offset 0x6A61 5644 bytes
font_01_sfnt_off00007d82.bin
a278a36cbab7bf6fa2581f894d1e3cbcd0ed7aa4c5d099820bbc0c7b1a9970b8
pdf-font-stream PDF embedded font (sfnt) at offset 0x7D82 9952 bytes