Malicious PDF — malware analysis report

Static analysis result for SHA-256 88a5253dff587427…

MALICIOUS

PDF

36.6 KB Created: 2020-08-31 08:49:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 31da659c498e34b01e55fcff4fecc746 SHA-1: 13dbff0581dea203c57b5d7cd98694d8b5016a06 SHA-256: 88a5253dff58742705e577d4a768877cf74f86eff74d7def68c3f164f2d48b44
152 Risk Score

Malware Insights

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

The PDF contains a heuristic firing for a malicious redirector link, which is also present in the document body. This link, 'https://ttraff.cc/wix?keyword=critical+thinking+bassham+5th+editio', is likely used to redirect the user to a malicious site. The document also exhibits characteristics of a link farm, with numerous embedded URLs pointing to Shopify and other benign-looking domains, likely to improve search engine ranking for the lure content. No scripts were extracted, and the document body is heavily obfuscated, but the presence of the malicious redirector is a strong indicator of malicious intent.

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.cc/wix?keyword=critical+thinking+bassham+5th+editio
    • https://cdn.shopify.com/s/files/1/0431/9408/9635/files/55948632031.pdf
    • https://cdn.shopify.com/s/files/1/0437/8981/1861/files/6739117122.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/59022585862.pdf
    • https://cdn.shopify.com/s/files/1/0432/6975/0944/files/richard_branson_autobiography.pdf
    • https://cdn.shopify.com/s/files/1/0440/3727/5813/files/29798793985.pdf
    • https://static.usrfiles.com/ugd/7f46b5_bc1340b218004f8da0ef2fa7fa943eec.pdf
    • https://static.usrfiles.com/ugd/857e61_b29a488589074828920e63d60dba5988.pdf
    • https://cdn.shopify.com/s/files/1/0434/3565/5335/files/alimentos_que_contienen_antioxidantes.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/71482320097.pdf
    • https://cdn.shopify.com/s/files/1/0429/5419/5097/files/778267402.pdf
    • https://cdn.shopify.com/s/files/1/0429/0638/6595/files/zewezotafisojin.pdf
    • https://cdn.shopify.com/s/files/1/0437/6972/5080/files/90893684352.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_off00004f1b.bin
eda563751108a3793b9171698c82dd88a87ab528d56fbe70ce0a12b47ccfc41d
pdf-font-stream PDF embedded font (sfnt) at offset 0x4F1B 5584 bytes
font_01_sfnt_off000061d9.bin
8d2efb290c352469f8ad5d4c0c3a9fdf753c03daf852b472aa2b52566cd564b2
pdf-font-stream PDF embedded font (sfnt) at offset 0x61D9 10564 bytes