Malicious PDF — malware analysis report

Static analysis result for SHA-256 665628b4c47f28bd…

MALICIOUS

PDF

40.6 KB Created: 2020-08-19 03:09:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e87730a9a6ea4d5d5a6310c2ebcd33b3 SHA-1: 90429d90c7b1798b8f03dd7fb9aa2f36c9fff714 SHA-256: 665628b4c47f28bd7c381693a5734b3a0544f23ff1550627257e5ec491a25700
154 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and heuristics indicate it contains a malicious redirector link and a large number of external PDF links, suggesting a link farm or SEO abuse. The document body, though heavily obfuscated, contains the malicious URL and several other Shopify-hosted PDF links. The presence of embedded URLs and the malicious redirector strongly suggest an attempt to lure users to malicious content, likely as part of a phishing or malware distribution campaign.

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/pify?keyword=brampton+manor+sixth+form+admissions
    • http://files.kaurpsychiatric.com/uploads/1/3/2/6/132682040/zikamof.pdf
    • http://files.petercolefriedman.com/uploads/1/3/0/7/130776619/639a193c08bf04.pdf
    • http://files.alamedhirudotherapy.org/uploads/1/3/0/7/130740213/5196133.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0435/2658/6527/files/companion_planting_vegetables.pdf
    • https://cdn.shopify.com/s/files/1/0434/1976/2840/files/two_digit_multiplication_worksheets_3rd_grade.pdf
    • https://cdn.shopify.com/s/files/1/0431/4248/0021/files/gekonokekopefitaril.pdf
    • https://cdn.shopify.com/s/files/1/0435/9448/1821/files/91627441228.pdf
    • https://cdn.shopify.com/s/files/1/0431/4424/9504/files/44972143631.pdf
    • https://cdn.shopify.com/s/files/1/0429/2637/5071/files/nexofuxumi.pdf
    • https://cdn.shopify.com/s/files/1/0437/5812/5207/files/48516341217.pdf
    • https://cdn.shopify.com/s/files/1/0430/2392/5402/files/pirepixawo.pdf
    • https://cdn.shopify.com/s/files/1/0428/0641/1431/files/31619972216.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_off00005fee.bin
b1d159239bd88d1b4e234d3f295f079ac209696895a213b4a710785214729215
pdf-font-stream PDF embedded font (sfnt) at offset 0x5FEE 5364 bytes
font_01_sfnt_off000071f8.bin
047c2c69d2aefe07f8afd8c6d4c0bb29cc7b33997e1ae5795b3d0057d999a79c
pdf-font-stream PDF embedded font (sfnt) at offset 0x71F8 10464 bytes