Malicious PDF — malware analysis report

Static analysis result for SHA-256 1924bd75a48d3f24…

MALICIOUS

PDF

36.5 KB Created: 2020-08-10 07:19:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7afd51493d4a206c9413870c89b58fe3 SHA-1: a6e4c4de2a13beb7ec40382d89152711e577d491 SHA-256: 1924bd75a48d3f2468a41c65e94f8b2baa1d379d1e1f3a90065d001d43e387c8
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains a large number of embedded links, many of which point to external PDF files, suggesting a link farm for SEO manipulation. One prominent URL, 'https://ttraff.ru/pify?keyword=medical+encyclopedia+pdf+free+download', is identified as a malicious redirector. The document body, though heavily obfuscated, also contains this URL, indicating an attempt to lure users to malicious infrastructure under the guise of providing free PDF downloads.

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=medical+encyclopedia+pdf+free+download
    • http://files.nirunutrition.com/uploads/1/3/0/8/130814052/1316723.pdf
    • http://files.jvonhdesigns.com/uploads/1/3/0/8/130814868/26e94e.pdf
    • http://files.troop3mbts.com/uploads/1/3/0/9/130969731/tilapujedasimuvuxud.pdf
    • http://files.made2measurehomerenovations.com/uploads/1/3/1/4/131453453/487126f3707.pdf
    • http://ribalo.bigislandbeekeepers.com/uploads/1/3/0/8/130874655/e14d6a5593.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0432/0549/2904/files/nupipa.pdf
    • https://cdn.shopify.com/s/files/1/0430/2825/0781/files/67703209997.pdf
    • https://cdn.shopify.com/s/files/1/0433/9010/7815/files/vampire_the_masquerade_core_rulebook.pdf
    • https://cdn.shopify.com/s/files/1/0440/0631/0046/files/zijafawoga.pdf
    • https://cdn.shopify.com/s/files/1/0430/4781/3269/files/wukazab.pdf
    • https://cdn.shopify.com/s/files/1/0431/3330/4986/files/99479528098.pdf
    • https://cdn.shopify.com/s/files/1/0433/5170/3706/files/gikofajijipoda.pdf
    • https://cdn.shopify.com/s/files/1/0429/2873/4367/files/pdf_file_attachment_settings.pdf
    • https://cdn.shopify.com/s/files/1/0433/7133/1734/files/77235689059.pdf
    • https://cdn.shopify.com/s/files/1/0431/0650/0769/files/impact_of_bullying_in_schools.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_off000050ce.bin
cafbf4e3f284e05f26de8ef1c4cd55f7ace180ba4769def0fe048ea063a3b11f
pdf-font-stream PDF embedded font (sfnt) at offset 0x50CE 5168 bytes
font_01_sfnt_off00006296.bin
da1bca36ad7fd85d9b3f5ef8301efac42d396a535c1dd2186ae777023d5e9a39
pdf-font-stream PDF embedded font (sfnt) at offset 0x6296 10152 bytes