Malicious PDF — malware analysis report

Static analysis result for SHA-256 8755633c8f7b6bab…

MALICIOUS

PDF

32.1 KB Created: 2020-08-18 21:17:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 53b2b8742e24551ef29d4ab257a08599 SHA-1: c50988bad04ca665564428fb3f51fb91b5fd86fe SHA-256: 8755633c8f7b6bab1675ad00cc20b0730bc104996b4eba5f75835f8129840b27
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 external PDF files, suggesting a link farm or redirection scheme. One critical heuristic identified a link to known malicious redirector infrastructure, specifically `https://ttraff.cc/pify?keyword=chesterton+601+datasheet`. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains references to the datasheet and the tool used to generate the PDF, which are likely decoys for the malicious links.

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.cc/pify?keyword=chesterton+601+datasheet
    • http://dikizef.lasalservices.com/uploads/1/3/1/6/131637136/dasapilu.pdf
    • http://puwubu.jwesleyfoundation.com/uploads/1/3/0/9/130969465/8680529.pdf
    • http://files.grayfurnaceman.com/uploads/1/3/0/7/130775850/462186.pdf
    • http://files.hillmarfarm.com/uploads/1/3/1/8/131856186/5b5ee94.pdf
    • http://files.annjamescounseling.com/uploads/1/3/2/6/132681910/829544.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0429/3001/2316/files/jijiramirotunugiwoda.pdf
    • https://cdn.shopify.com/s/files/1/0431/7465/8197/files/64764980765.pdf
    • https://cdn.shopify.com/s/files/1/0433/5815/9006/files/96895494284.pdf
    • https://cdn.shopify.com/s/files/1/0430/0118/4417/files/bajaraxomegonudijif.pdf
    • https://cdn.shopify.com/s/files/1/0432/7741/8656/files/rovizotifuwuluw.pdf
    • https://cdn.shopify.com/s/files/1/0434/4017/7308/files/56896125691.pdf
    • https://cdn.shopify.com/s/files/1/0431/8347/2791/files/39386483874.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/78683638278.pdf
    • https://cdn.shopify.com/s/files/1/0427/9848/1564/files/ferorotaginawumux.pdf
    • https://cdn.shopify.com/s/files/1/0428/2135/3639/files/apostila_autocad_civil_3d_2020.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_off00004240.bin
c56ca1e3e2f82c0d9e7939a8c4bc153f5ecf6072b007c414f5fbf876389b72b3
pdf-font-stream PDF embedded font (sfnt) at offset 0x4240 5132 bytes
font_01_sfnt_off000053af.bin
a668e696bf992531355756d605ea03c010b3fda8904f805fdef0a65931351ecb
pdf-font-stream PDF embedded font (sfnt) at offset 0x53AF 9504 bytes