Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf668085ce3e3d64…

MALICIOUS

PDF

46.0 KB Created: 2020-08-19 07:57:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 285520441fb075aa09976c26dcb782f3 SHA-1: 08b96c405cb697d49a2845b781ea0ff1e1616f34 SHA-256: cf668085ce3e3d64939900cc37e98391181d93fa002e280cc79b2abfabb6b82f
154 Risk Score

Malware Insights

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

The PDF contains a mass external link farm designed to redirect users to malicious infrastructure, as indicated by the PDF_SEO_LINK_FARM and PDF_MALICIOUS_REDIRECTOR_LINK heuristics. The primary malicious URL identified is https://ttraff.ru/pify?keyword=common+themes+in+literature+pdf. The document body is heavily obfuscated but contains references to the redirector URL. The ML classifier also 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=common+themes+in+literature+pdf
    • http://madof.candlesbybarwick.com/uploads/1/3/1/4/131437823/fipafaxipiwivosakuv.pdf
    • http://files.valleyliberator.com/uploads/1/3/1/6/131606035/padavosagog.pdf
    • http://files.thedrewdrake.com/uploads/1/3/1/6/131606453/4ac4b28.pdf
    • http://files.jdudleysmith-acupuncture.com/uploads/1/3/0/7/130776381/tupinob.pdf
    • http://files.guskampfans.com/uploads/1/3/0/9/130968988/nijolesejisow.pdf
    • https://cdn.shopify.com/s/files/1/0430/9604/7783/files/catalasa_en_plantas.pdf
    • https://cdn.shopify.com/s/files/1/0439/5941/9038/files/child_psychology_topics.pdf
    • https://cdn.shopify.com/s/files/1/0431/8494/7357/files/28506823914.pdf
    • https://cdn.shopify.com/s/files/1/0436/0133/0339/files/armory_v._delamirie.pdf
    • https://cdn.shopify.com/s/files/1/0436/7171/5993/files/math_games_book.pdf
    • https://cdn.shopify.com/s/files/1/0434/6108/3301/files/lufareve.pdf
    • https://cdn.shopify.com/s/files/1/0430/0305/2191/files/el_alcoholismo_consecuencias_y_prevencin.pdf
    • https://cdn.shopify.com/s/files/1/0435/3058/4213/files/ctet_answer_key_2020_set_s.pdf
    • https://cdn.shopify.com/s/files/1/0435/1698/5503/files/blackberry_android_9_pie.pdf
    • https://cdn.shopify.com/s/files/1/0432/3111/7467/files/16870462322.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_off0000762a.bin
b151a2b65d30e7b348fb6e5bc9c7733e1eab688f2c803aeabc705a8fc9787488
pdf-font-stream PDF embedded font (sfnt) at offset 0x762A 5188 bytes
font_01_sfnt_off00008799.bin
fd016f49880352432535185f95493f68af3db775a5e5903c79cb81943b073b43
pdf-font-stream PDF embedded font (sfnt) at offset 0x8799 10488 bytes