Malicious PDF — malware analysis report

Static analysis result for SHA-256 c862b66ad2b2e747…

MALICIOUS

PDF

39.0 KB Created: 2020-08-04 01:14:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: eb36adcb7d7910ea10d8083bf4d0f736 SHA-1: c3a129a312910c0a58438cdc75ba9723a8c2e044 SHA-256: c862b66ad2b2e74768f2fb2e3bd11c0efb5206d66deee239d8c371b6f6bcd207
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, including one pointing to a known malicious redirector. The document body, though heavily obfuscated, contains the same URL and other links that appear to be part of a link farm designed to improve search engine ranking for malicious content. The ML classifier strongly indicates 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=introduction+to+structural+dynamics+and+aeroelasticity+pdf
    • http://files.orizoncenter.net/uploads/1/3/0/7/130739598/sunaziboj.pdf
    • http://files.g-n-o.com/uploads/1/3/1/3/131383651/3999457.pdf
    • http://files.selfbookshelf.org/uploads/1/3/1/4/131437724/33437f19753f5bb.pdf
    • https://cdn.shopify.com/s/files/1/0437/1621/4936/files/vuligunipe.pdf
    • https://cdn.shopify.com/s/files/1/0427/8052/4710/files/tuwapebedo.pdf
    • https://cdn.shopify.com/s/files/1/0428/8937/9993/files/25030302187.pdf
    • https://cdn.shopify.com/s/files/1/0431/3595/9202/files/41025231409.pdf
    • https://cdn.shopify.com/s/files/1/0428/3963/8179/files/xurizirigobale.pdf
    • https://cdn.shopify.com/s/files/1/0432/8351/3494/files/posadafip.pdf
    • https://cdn.shopify.com/s/files/1/0434/1704/3111/files/jefizikive.pdf
    • https://cdn.shopify.com/s/files/1/0431/6869/4423/files/14828669340.pdf
    • https://cdn.shopify.com/s/files/1/0434/7186/3961/files/ludinexokezuraritu.pdf
    • https://cdn.shopify.com/s/files/1/0435/0767/9397/files/36581880583.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/37278413385.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/duliwoledemovaj.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_off00005a14.bin
ab47c047de018a47b9f3349deb526f6e01c95ee4f8c9784b3380f6b8f832154a
pdf-font-stream PDF embedded font (sfnt) at offset 0x5A14 5340 bytes
font_01_sfnt_off00006c30.bin
45df54bf863396d8365285794890818f90bff175d6147a9cb044e9623437e682
pdf-font-stream PDF embedded font (sfnt) at offset 0x6C30 10128 bytes