Malicious PDF — malware analysis report

Static analysis result for SHA-256 687c0beba45b2545…

MALICIOUS

PDF

32.2 KB Created: 2020-08-15 03:35:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 65a92817f1812a0a6f81cd9da3d94c6c SHA-1: db1305d7e54ff0a124f8e9c401b6bfed5ddeb7d0 SHA-256: 687c0beba45b25458521c6a1e7a9683874123bfcbd2005170aea10991c381e8f
162 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded links, many of which point to a link farm hosted on Shopify. One prominent link redirects through `ttraff.ru`, a known malicious redirector, to a document related to 'simple past mixed exercises'. The presence of a 'download button' lure and the ML classifier's high confidence score indicate a malicious intent to redirect users to potentially harmful content. No scripts were extracted, but the PDF structure itself facilitates the malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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=simple+past+mixed+exercises+with+answers
    • http://files.parentsoftransgenderkids.org/uploads/1/3/0/8/130814553/zabilix_riwigas_wovetok.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0429/1775/7095/files/complements_in_binary_number_system.pdf
    • https://cdn.shopify.com/s/files/1/0434/2687/3509/files/catalogue_n_philips_2020.pdf
    • https://cdn.shopify.com/s/files/1/0435/7645/9422/files/63216517328.pdf
    • https://cdn.shopify.com/s/files/1/0430/4030/9402/files/1586790957.pdf
    • https://cdn.shopify.com/s/files/1/0428/0533/0083/files/pugojor.pdf
    • https://cdn.shopify.com/s/files/1/0440/3917/6342/files/easy-_webprint_ex.pdf
    • https://cdn.shopify.com/s/files/1/0431/5414/5444/files/week_in_a_year.pdf
    • https://cdn.shopify.com/s/files/1/0431/6112/5025/files/10177498691.pdf
    • https://cdn.shopify.com/s/files/1/0433/3414/0056/files/76077107679.pdf
    • https://cdn.shopify.com/s/files/1/0432/0054/4931/files/6055268703.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_off00003f45.bin
fcc5b54b54f5fc9bbfebc11cf80f8c14cbe4ce52d022f3ebf04cb7364cc47e3b
pdf-font-stream PDF embedded font (sfnt) at offset 0x3F45 5576 bytes
font_01_sfnt_off00005220.bin
cbef4a9288e14de15f5b058d22ce7ed5a7890327d97dc4f55caf8ee0c7e6bd04
pdf-font-stream PDF embedded font (sfnt) at offset 0x5220 9968 bytes