Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a497a8f6704bdb5…

MALICIOUS

PDF

43.9 KB Created: 2020-08-21 00:11:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2701c6adae2fcdc158c0b68ba2df36ce SHA-1: f705d8219a7e7e7fe894cb82c7670a3a7db57461 SHA-256: 4a497a8f6704bdb5cfe1386ff27c52cc42ace94da6c3f9f4cb260ce6ef13bb15
154 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.ru, which is disguised as an 'automatic reply vacation template'. The document also hosts a large number of other PDF files on Shopify domains, likely as part of a link farm to improve search engine ranking for malicious content. The ML classifier strongly indicated 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/pify?keyword=automatic+reply+vacation+template
    • http://files.altonmillpondhockey.ca/uploads/1/3/0/7/130775561/losegogipise-bibibun-vigiporukumujef-lapumuro.pdf
    • http://files.lacadultliteracy.org/uploads/1/3/0/8/130815115/2ba56510f4be17c.pdf
    • https://cdn.shopify.com/s/files/1/0443/9543/0054/files/acca_f5_study_guide.pdf
    • https://cdn.shopify.com/s/files/1/0439/3887/3512/files/rasukojofuforo.pdf
    • https://cdn.shopify.com/s/files/1/0429/8942/0695/files/eenadu_epaper_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0434/5846/1863/files/dissociation_of_acids_and_bases_worksheet_answers.pdf
    • https://cdn.shopify.com/s/files/1/0434/3191/9765/files/zerijisoxesusexiwe.pdf
    • https://cdn.shopify.com/s/files/1/0428/6034/7551/files/vojejunoxigirodulu.pdf
    • https://cdn.shopify.com/s/files/1/0432/7519/0422/files/99963018512.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/65621046881.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/9284441163.pdf?v=1594212706
    • https://cdn.shopify.com/s/files/1/0449/7352/3112/files/cell_cycle_mcq_with_answers.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_off00006f00.bin
4ab5a49aeb26455f087cf75abe995460aabb974c8f58b3726bf6d83be1507743
pdf-font-stream PDF embedded font (sfnt) at offset 0x6F00 5052 bytes
font_01_sfnt_off00008022.bin
7bffcde65b7bd174f4f993a1524a64d11419eb8cc2364de1b4d6c82f4b3d31a9
pdf-font-stream PDF embedded font (sfnt) at offset 0x8022 10088 bytes