Malicious PDF — malware analysis report

Static analysis result for SHA-256 e66a9343ce69afe3…

MALICIOUS

PDF

39.9 KB Created: 2020-08-29 09:00:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 31f99da027306d70dd5fad72bb05cbd4 SHA-1: e1dd793f2eda6c0695b9638c4a36f9fef7126090 SHA-256: e66a9343ce69afe3746509ef07274115276f5604e70fea79e52e49f015c86e90
152 Risk Score

Malware Insights

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

The PDF file was flagged by multiple critical heuristics for containing malicious redirector links and a large number of embedded external links, suggesting a link farm for SEO manipulation or malware distribution. The ML classifier also strongly indicated maliciousness. The primary malicious IOC is the redirector URL, which is likely used to funnel victims to a malicious site. No scripts were extracted, but the PDF structure itself is indicative of a malicious lure.

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=reading+comprehension+test+2+eso+pdf
    • https://cdn.shopify.com/s/files/1/0438/4007/7981/files/65962265572.pdf
    • https://cdn.shopify.com/s/files/1/0439/6145/0654/files/dugugigasarozoke.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/15138334831.pdf
    • https://cdn.shopify.com/s/files/1/0437/7909/6728/files/33039391370.pdf
    • https://static.usrfiles.com/ugd/b8c837_e1b9eaafee024ac588beca8e65b2ae98.pdf
    • https://static.usrfiles.com/ugd/b8c837_eede28d44e994ed8ba76f8573931113b.pdf
    • https://static.usrfiles.com/ugd/b8c837_9e88968d59744da3964ca22d0488171b.pdf
    • https://static.usrfiles.com/ugd/b8c837_5e117074dfaf411d888b606c2b7bed3b.pdf
    • https://static.usrfiles.com/ugd/b8c837_857fd19f984e4c0fa702c7e3211b0246.pdf
    • https://cdn.shopify.com/s/files/1/0436/8180/8549/files/prebles_artforms_12th_edition.pdf
    • https://cdn.shopify.com/s/files/1/0437/7221/5448/files/ejercicios_resueltos_de_algebra_booleana.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_off00005cac.bin
13992e9ea66bd3ceb64d6c8f1ea8ea6a4874a0f0c6cd801336ca81943e2516a8
pdf-font-stream PDF embedded font (sfnt) at offset 0x5CAC 5676 bytes
font_01_sfnt_off00006fc8.bin
6a62f5c250e358874633f6d3ebffbdc3e28262c17f4be55a9f1cf60c85264e4a
pdf-font-stream PDF embedded font (sfnt) at offset 0x6FC8 10288 bytes