Malicious PDF — malware analysis report

Static analysis result for SHA-256 73b3c4056cf942e4…

MALICIOUS

PDF

46.4 KB Created: 2020-08-14 13:57:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f54d35b8bd815b497abd14c3e9536ee6 SHA-1: fedc2fe2b218f2fd20eb48c363a2d53b50200216 SHA-256: 73b3c4056cf942e4b3fabfcfa5fe9a629c284408ad086881604cfcfc36c78f65
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many of which point to external PDF files hosted on various domains. One of these links, https://ttraff.ru/wb?keyword=coordinacion%20oculo%20manual%20infantil, is flagged as a known malicious redirector. This suggests the document is designed to lure users into clicking through a chain of links, ultimately leading them to malicious infrastructure.

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=coordinacion%20oculo%20manual%20infantil
    • http://files.valmalencoalpina.com/uploads/1/3/1/6/131607440/266657.pdf
    • http://files.stelizabethrap.com/uploads/1/3/0/8/130815026/823279.pdf
    • http://files.thebrainyblonde.com/uploads/1/3/1/4/131437005/3296376.pdf
    • http://zudis.northwoodslearninghub.com/uploads/1/3/1/6/131606617/547970.pdf
    • http://files.getyourstarterkit.com/uploads/1/3/1/6/131607164/kugonifowopabos.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0436/0686/8126/files/mewumo.pdf
    • https://cdn.shopify.com/s/files/1/0433/7221/6483/files/90990804965.pdf
    • https://cdn.shopify.com/s/files/1/0438/7222/3387/files/natezujoxabidixa.pdf
    • https://cdn.shopify.com/s/files/1/0429/7133/2767/files/livro_para_aprender_espanhol.pdf
    • https://cdn.shopify.com/s/files/1/0449/5425/5515/files/unity_clamp_rotation.pdf
    • https://cdn.shopify.com/s/files/1/0433/2240/9125/files/skeleton_shirt_template_printable.pdf
    • https://cdn.shopify.com/s/files/1/0439/1036/5339/files/statistical_modelling_in_pharmaceutical_research_and_development.pdf
    • https://cdn.shopify.com/s/files/1/0431/3268/2397/files/80552303168.pdf
    • https://cdn.shopify.com/s/files/1/0430/7392/9378/files/cartesian_product_of_sets.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_off000076cb.bin
1c1b7958cd4a3137d2a57a6b87108f624aa2250373fe0ad518301e3815baeb02
pdf-font-stream PDF embedded font (sfnt) at offset 0x76CB 4896 bytes
font_01_sfnt_off0000875a.bin
ed3ca526dbe4766bbf2821b307b6f2198f517e70031dfcc4e7dd4a3acb0597c3
pdf-font-stream PDF embedded font (sfnt) at offset 0x875A 11060 bytes