Malicious PDF — malware analysis report

Static analysis result for SHA-256 68246c31db4885ed…

MALICIOUS

PDF

44.4 KB Created: 2020-08-29 08:06:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 467e692ffb78b01f12aa359c21d11fb0 SHA-1: 374905772d31e15910d9041b2dfef2a500495f17 SHA-256: 68246c31db4885ed75b4a785101ca885076422c208efd40aaff554be2ed71f69
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to benign educational resources, but one critical link directs to a known malicious redirector. The document body, though heavily obfuscated, contains the URL 'https://ttraff.cc/wix?keyword=exercicios+sistema+nervoso+com+gabarito+5+ano', suggesting a lure to disguise malicious activity as educational content. The ML classifier strongly flagged this PDF as malicious.

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=exercicios+sistema+nervoso+com+gabarito+5+ano
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/b8c837_f04bc6cc14134a9d88ae5f999e61f6dc.pdf
    • https://static.usrfiles.com/ugd/b8c837_678b410e24c54e6499218565f5441258.pdf
    • https://static.usrfiles.com/ugd/b8c837_f7378adc4b584a5d90ec85cc30d9aa8b.pdf
    • https://cdn.shopify.com/s/files/1/0435/6784/1443/files/basic_formula_of_maths.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/tanedikefiresemur.pdf
    • https://cdn.shopify.com/s/files/1/0432/7833/6165/files/26398734433.pdf
    • https://static.usrfiles.com/ugd/b8c837_65a39bf7cc8b4d75bde40997dd21f0ee.pdf
    • https://static.usrfiles.com/ugd/b8c837_409c019efa9f4aa28a7a617c0d06b294.pdf
    • https://static.usrfiles.com/ugd/b8c837_2dcfd9fb9f47429f95d6340a8be0a926.pdf
    • https://static.usrfiles.com/ugd/b8c837_0cb1711f615347d2bd7a0b277cfc7a8f.pdf
    • https://static.usrfiles.com/ugd/b8c837_3bfb702965b1477b80a3483ce8996ab9.pdf
    • https://static.usrfiles.com/ugd/b8c837_a8c7aa945a4a4a84af789f6961c83760.pdf
    • https://static.usrfiles.com/ugd/b8c837_896367473ce44bd59dd3671ef063cd83.pdf
    • https://static.usrfiles.com/ugd/b8c837_b5ce2959be1140ceb0e46b680de0cc8e.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_off00006854.bin
3ee7286c15ec987cb7f0f652167e2b7cc53ffb583455920d588ec3371b3429a3
pdf-font-stream PDF embedded font (sfnt) at offset 0x6854 5436 bytes
font_01_sfnt_off00007ac7.bin
676beace997bb55d62ad22e33e7373fe19c2fc635aa0f70fc14400a9a834d8ff
pdf-font-stream PDF embedded font (sfnt) at offset 0x7AC7 13836 bytes