Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f988a27f7c73c42…

MALICIOUS

PDF

39.6 KB Created: 2020-08-31 00:49:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 27ceb2c531b55884f46f6b8d737f2da3 SHA-1: f4ecb83fa37aa2cb280e2502565cd4d2b2173bb8 SHA-256: 1f988a27f7c73c42d8e231fedd5c6389fe192dfba901f2d62c54cedf40dae76c
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a malicious redirector link disguised as a 'Kubota b2320 parts manual'. This link, 'https://ttraff.ru/wix?keyword=kubota+b2320+parts+manual', is identified as a critical threat. The document also exhibits characteristics of a link farm, with numerous embedded URLs pointing to external PDFs, likely for SEO manipulation to increase visibility. The ML classifier strongly supports the malicious nature of this PDF.

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/wix?keyword=kubota+b2320+parts+manual
    • https://cdn.shopify.com/s/files/1/0432/9085/3531/files/19828868487.pdf
    • https://cdn.shopify.com/s/files/1/0440/4084/7510/files/clek_foonf_guide.pdf
    • https://cdn.shopify.com/s/files/1/0433/0127/3750/files/analytical_method_validation_acceptance_criteria.pdf
    • https://static.usrfiles.com/ugd/5fd5c1_3e1962a8183b4810bdda6cde407fc694.pdf
    • https://static.usrfiles.com/ugd/b8c837_bb27de6cef0b4598afe0d75b800c6143.pdf
    • https://cdn.shopify.com/s/files/1/0438/8293/8520/files/ijazat_movie_songs_ming.pdf
    • https://cdn.shopify.com/s/files/1/0432/2381/0211/files/93345159740.pdf
    • https://cdn.shopify.com/s/files/1/0431/1144/8729/files/9051665124.pdf
    • https://cdn.shopify.com/s/files/1/0427/7351/2359/files/21534496753.pdf
    • https://cdn.shopify.com/s/files/1/0471/0619/5606/files/43978912978.pdf
    • https://cdn.shopify.com/s/files/1/0437/6225/3978/files/wiwepomikuwubuxebad.pdf
    • https://cdn.shopify.com/s/files/1/0433/0668/0484/files/beauty_and_the_beast_2020.pdf
    • https://cdn.shopify.com/s/files/1/0431/5843/8039/files/18933837088.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_off00005b7e.bin
fde5b6e1117fb9ee29d8c5523d65c3717ea8ce650c4054a239780e24827f1dc2
pdf-font-stream PDF embedded font (sfnt) at offset 0x5B7E 5512 bytes
font_01_sfnt_off00006e17.bin
b0ed3dd1f62f203d951835b30d70e8b4aeacce2f2c92250625698cfcc15bdcb1
pdf-font-stream PDF embedded font (sfnt) at offset 0x6E17 10500 bytes