Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b341e4c0f6021c7…

MALICIOUS

PDF

41.4 KB Created: 2020-08-30 03:26:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d6f7707bc7daf5f0492e075085eae847 SHA-1: 3bf3c2a77d83af156f68ab5872fb3baafde9e505 SHA-256: 4b341e4c0f6021c7ed8b58db762aadae99c7c903e036196990da1db8e473d3e4
152 Risk Score

Malware Insights

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

The PDF file contains numerous embedded links, with one specifically identified as a malicious redirector. The document body, though partially corrupted, includes the URL 'https://ttraff.ru/wix?keyword=oxford+dictionary+english+to+english', which is flagged as malicious. Additionally, the file exhibits characteristics of a link farm, with many links pointing to Shopify domains, suggesting an attempt to obscure the malicious intent or distribute content. The ML classifier strongly indicates maliciousness.

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=oxford+dictionary+english+to+english
    • https://cdn.shopify.com/s/files/1/0449/5595/9464/files/surah_yasin_sharif.pdf
    • https://cdn.shopify.com/s/files/1/0432/0670/5312/files/35206812888.pdf
    • https://cdn.shopify.com/s/files/1/0430/9378/6791/files/lowes_culpeper_va.pdf
    • https://cdn.shopify.com/s/files/1/0437/8443/7922/files/project_on_social_issues.pdf
    • https://cdn.shopify.com/s/files/1/0437/0831/7850/files/audio_cutter_app.pdf
    • https://cdn.shopify.com/s/files/1/0430/0334/7098/files/79516545124.pdf
    • https://cdn.shopify.com/s/files/1/0437/2935/4903/files/rufewaregi.pdf
    • https://cdn.shopify.com/s/files/1/0464/7383/8744/files/45446475005.pdf
    • https://cdn.shopify.com/s/files/1/0439/0505/6920/files/evaluating_rational_algebraic_expressions_worksheet.pdf
    • https://static.usrfiles.com/ugd/455f95_941a5bc4e55f49118df03cec54c0fb32.pdf
    • https://static.usrfiles.com/ugd/b65acf_2286c5d014c0473c862a029bce928637.pdf
    • https://static.usrfiles.com/ugd/b8c837_3f496e21c71f4133bbef8f40766c2897.pdf
    • https://static.usrfiles.com/ugd/b8c837_d72bf1bb1da8404abea58e9d5f721bac.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_off0000635d.bin
a1a5ca26d972f06dac99a394390705f5c8dc478622cf1b86aa7601bdb1cb775f
pdf-font-stream PDF embedded font (sfnt) at offset 0x635D 5480 bytes
font_01_sfnt_off00007607.bin
86ac85d5de3b667d24b981871a89a2285a1ee438ef86800d2b5ef5d854706853
pdf-font-stream PDF embedded font (sfnt) at offset 0x7607 10144 bytes