Malicious PDF — malware analysis report

Static analysis result for SHA-256 a178e8b7e7643a95…

MALICIOUS

PDF

36.0 KB Created: 2020-08-31 23:03:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c402eca4de959b05cf1fb2c1b8a8415c SHA-1: ffb67649a5b35e81f8f59f3371979c0847f85c2b SHA-256: a178e8b7e7643a95d4857dba49bc85422c401a2bf81b9d2970005eea3fe2a98b
150 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link pointing to 'https://ttraff.cc/wix?keyword=partitive+proportion+word+problems+worksheet'. Additionally, it exhibits a PDF link farm pattern, with numerous links to external PDFs, many hosted on Shopify. The ML classifier also strongly flagged this PDF as malicious. The document body text, though heavily obfuscated, contains the same malicious URL, suggesting an attempt to lure users to a malicious site under the guise of a worksheet.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 3

  • 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.
  • 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=partitive+proportion+word+problems+worksheet
    • https://cdn.shopify.com/s/files/1/0429/7211/9199/files/selikilunowizajokijumedor.pdf
    • https://cdn.shopify.com/s/files/1/0431/7170/9092/files/sovimopatugada.pdf
    • https://cdn.shopify.com/s/files/1/0431/0840/1306/files/logical_framework_analysis_example.pdf
    • https://static.usrfiles.com/ugd/b8c837_1e767dd5639445e2818aecc505d05f85.pdf
    • https://static.usrfiles.com/ugd/b8c837_654768dc757848ccb55b075d94197deb.pdf
    • https://cdn.shopify.com/s/files/1/0428/2092/7644/files/social_and_political_philosophy_classic_and_contemporary_readings.pdf
    • https://cdn.shopify.com/s/files/1/0429/6045/3785/files/docker_run_android_app.pdf
    • https://cdn.shopify.com/s/files/1/0431/8212/9320/files/pokemon_pearl_rom.pdf
    • https://cdn.shopify.com/s/files/1/0439/8442/1022/files/fojer.pdf
    • https://cdn.shopify.com/s/files/1/0439/0617/1048/files/25761995545.pdf
    • https://static.usrfiles.com/ugd/b8c837_db3c08653dbf460793325522e1576ce8.pdf
    • https://static.usrfiles.com/ugd/8b2c09_e63b95042e8043f38c72eef788c97dce.pdf
    • https://static.usrfiles.com/ugd/b7082a_5c68a71aa030407588f7d0c8bab1ea9a.pdf
    • https://static.usrfiles.com/ugd/26938b_c857b8b957ad431eb00bf4afac67b08a.pdf
    • https://static.usrfiles.com/ugd/724bd4_300224e46ea74fc098d71a09fc65c166.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_off00004e17.bin
8decd29ae1be4f47d97fdd9d43c0292de9a03972453e0ebaa70706d70af2c2e9
pdf-font-stream PDF embedded font (sfnt) at offset 0x4E17 5556 bytes
font_01_sfnt_off000060dd.bin
c0f3985e8f2ce9d44e79ad93e0db13e74cec33a9c233545888b18cd6603578d3
pdf-font-stream PDF embedded font (sfnt) at offset 0x60DD 10048 bytes