Malicious PDF — malware analysis report

Static analysis result for SHA-256 784f61bc0546b895…

MALICIOUS

PDF

40.4 KB Created: 2020-08-13 23:29:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: a8cfc5ddfd45f45c2f9a6dff1c7ebf60 SHA-1: c1517e70fa80344ed8f913ab93deafacc0e2516e SHA-256: 784f61bc0546b89578d0425473252fb86aa9604d4172d416bfa9d653f218a4ab
154 Risk Score

Malware Insights

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

The PDF contains a heuristic firing for malicious redirector links, pointing to 'https://ttraff.ru/pify?keyword=go+formative+answer+key'. The document body also contains this URL, presented as an 'answer key', indicating a social engineering lure. The PDF also contains a large number of external links, suggesting a link farm or SEO abuse tactic. The ML classifier strongly flagged this PDF as malicious.

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=go+formative+answer+key
    • http://files.almamusicstudio.com/uploads/1/3/1/4/131409693/2c72f055d632c0.pdf
    • http://files.mikekleeman.com/uploads/1/3/1/4/131437322/52202.pdf
    • http://files.rebeccalynnphotography.net/uploads/1/3/0/8/130874518/4840188.pdf
    • http://kulute.santafecommunityresource.org/uploads/1/3/1/3/131383562/7502225.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0438/3630/9666/files/2.pdf
    • https://cdn.shopify.com/s/files/1/0427/8714/3839/files/gekotirosabuwonu.pdf
    • https://cdn.shopify.com/s/files/1/0440/5726/4280/files/22433193693.pdf
    • https://cdn.shopify.com/s/files/1/0429/7919/7081/files/femiwexowakorokoma.pdf
    • https://cdn.shopify.com/s/files/1/0437/4292/0869/files/kofijukijunex.pdf
    • https://cdn.shopify.com/s/files/1/0431/6551/5933/files/bible_verses_download.pdf
    • https://cdn.shopify.com/s/files/1/0428/2122/2567/files/nbi_online_application_form.pdf
    • https://cdn.shopify.com/s/files/1/0429/3401/0015/files/white_zero_turn_mower.pdf
    • https://cdn.shopify.com/s/files/1/0431/9199/2480/files/nifozidebonakafitoluf.pdf
    • https://cdn.shopify.com/s/files/1/0431/6102/6719/files/full_ielts_academic_reading_test.pdf
    • https://cdn.shopify.com/s/files/1/0429/8863/4263/files/79800300633.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_off00006060.bin
1f0c1139b9c60de68a59c4c11571b0cf442c50c85a31ca808282183ffbbec673
pdf-font-stream PDF embedded font (sfnt) at offset 0x6060 5228 bytes
font_01_sfnt_off00007233.bin
b9fac1d1f198c509c3d5a9139db35a865faa44ebafb35779638a6691e08f97c8
pdf-font-stream PDF embedded font (sfnt) at offset 0x7233 10228 bytes