Malicious PDF — malware analysis report

Static analysis result for SHA-256 09c70fc5d6fccaf9…

MALICIOUS

PDF

42.9 KB Created: 2020-08-29 05:50:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cd5bc200f201974d0f7895be50f92a05 SHA-1: a2895daa44c3676ffd7045142ca28128fbbc4a8b SHA-256: 09c70fc5d6fccaf929c5a2285c3b71f02fd853e208a751bf46ab42d1df19ab09
154 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to a redirector service. The document body, though heavily obfuscated, contains a URL that appears to be a lure for 'nsk bearing replacement guide pdf'. The ML classifier strongly indicates maliciousness, and the presence of a redirector link suggests an attempt to lead the user to a malicious site.

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/wix?keyword=nsk+bearing+replacement+guide+pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/b8c837_55aefac4bb4040a7ad352026639c18a9.pdf
    • https://static.usrfiles.com/ugd/b8c837_1deed982071a48139a93912da9e86076.pdf
    • https://static.usrfiles.com/ugd/b8c837_f8bcfb6edb6f4ee89012a1a3fcc13600.pdf
    • https://static.usrfiles.com/ugd/b8c837_1a894635b6aa4afaa3b674279dc55d6f.pdf
    • https://static.usrfiles.com/ugd/b8c837_bb7553ecb1ec4367884471ef84d1f983.pdf
    • https://static.usrfiles.com/ugd/b8c837_9af6a01153da4800bb69aa80a8cf6f5b.pdf
    • https://static.usrfiles.com/ugd/b8c837_ed2ec2532ab9414db6307d41b171cbf8.pdf
    • https://cdn.shopify.com/s/files/1/0440/7849/7944/files/sediwakuzugeladoraluju.pdf
    • https://cdn.shopify.com/s/files/1/0434/0878/5562/files/87355578116.pdf
    • https://cdn.shopify.com/s/files/1/0430/5498/9466/files/4008-_101-_a65.pdf
    • https://cdn.shopify.com/s/files/1/0431/5817/5893/files/google_chrome_para_kali_linux.pdf
    • https://cdn.shopify.com/s/files/1/0429/1015/4908/files/clang_implicit_instantiation_of_undefined_template.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_off00006173.bin
f639fbd353e4eb99d3a300124c76177138c533b89ac1949a59f9bc4f35edd726
pdf-font-stream PDF embedded font (sfnt) at offset 0x6173 5648 bytes
font_01_sfnt_off00007491.bin
002953d4b2cb1010081c11d1865d6b569c1caafec4b25f77253bdccddbd91006
pdf-font-stream PDF embedded font (sfnt) at offset 0x7491 13392 bytes