Malicious PDF — malware analysis report

Static analysis result for SHA-256 87238710cc6c96a9…

MALICIOUS

PDF

40.1 KB Created: 2020-08-13 17:46:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e4c9f3f3a847d11a923096526a684e44 SHA-1: c65ca7bdba98c8e462dffad11e48a727fdac14ec SHA-256: 87238710cc6c96a996b0769f195f4174d39a818b6b656161457bbc025183a58c
154 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.ru, which is likely used to obscure the final destination of the malicious payload. The document body, though heavily obfuscated, contains references to worksheets and educational materials, suggesting a lure to entice users to click the malicious link. The ML classifier strongly indicates maliciousness, and the presence of numerous external links points to a link farm or SEO poisoning attempt.

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/wb?keyword=unifix%20cubes%20worksheets%20free
    • http://files.heartlandarchery.ca/uploads/1/3/2/3/132302907/bubutoxitag.pdf
    • http://fodala.agratefulnote.com/uploads/1/3/0/7/130738614/ketixuboxi_tasora.pdf
    • http://files.natteyallockps.com/uploads/1/3/2/7/132740584/durukugol.pdf
    • http://ritagogaw.laurenparker.com.au/uploads/1/3/1/6/131606289/86a7d340706.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0437/0310/7752/files/livro_associativismo_e_cooperativismo.pdf
    • https://cdn.shopify.com/s/files/1/0439/4539/4331/files/anil_s_ghost_full_text.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/64541570927.pdf
    • https://cdn.shopify.com/s/files/1/0432/2109/0471/files/konofedivumasatapus.pdf
    • https://cdn.shopify.com/s/files/1/0438/9522/6523/files/gezesuxurad.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/mozesuseb.pdf
    • https://cdn.shopify.com/s/files/1/0428/5346/6271/files/21073297356.pdf
    • https://cdn.shopify.com/s/files/1/0435/5286/6467/files/carencia_de_vitamina_k.pdf
    • https://cdn.shopify.com/s/files/1/0429/6661/4175/files/thinking_in_java_latest_edition.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_off00005d64.bin
9d35024421ef6286df4d7c418a6b298b783b03a01accb92b6ec7bad7e0cc0805
pdf-font-stream PDF embedded font (sfnt) at offset 0x5D64 5080 bytes
font_01_sfnt_off00006ec0.bin
ef6914e651ac15f5934d05270bd88f0323b8348982695256f0679a5b6354d5cb
pdf-font-stream PDF embedded font (sfnt) at offset 0x6EC0 10932 bytes