Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3e4cbc7640feca1…

MALICIOUS

PDF

35.3 KB Created: 2020-08-08 16:30:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c1cd10defa3b4767efb2869bba3fd444 SHA-1: e0cb141a82744758c9166840ec4d78feab20e4be SHA-256: a3e4cbc7640feca15f3e76cdab4265a04a4047d61a1b4c3b54aa5b072849873b
150 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a high density of external links, many pointing to what appears to be a link farm designed for SEO manipulation. One prominent link, 'https://ttraff.cc/pify?keyword=oxford+bookworms+library+stage+1+the+wizard+of+oz+pdf', is flagged as a malicious redirector. The document body, though heavily obfuscated, contains text related to 'Oxford bookworms library' and the 'wizard of oz', suggesting a lure to disguise the malicious intent. The ML classifier also strongly indicated maliciousness.

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/pify?keyword=oxford+bookworms+library+stage+1+the+wizard+of+oz+pdf
    • http://files.hollyboyter.com/uploads/1/3/2/6/132695741/33fbe27b7e057.pdf
    • http://files.studio11sfe.com/uploads/1/3/2/3/132303068/rerosiz.pdf
    • http://files.positivelypolyanna.net/uploads/1/3/0/9/130969390/vinopojonapolup-pefamepi.pdf
    • http://files.davidrjohnsantiques.com/uploads/1/3/0/8/130814192/3831470.pdf
    • https://cdn.shopify.com/s/files/1/0427/8134/3900/files/python_str_object_is_not_callable.pdf
    • https://cdn.shopify.com/s/files/1/0432/0896/6301/files/pobefimowelebonisiluv.pdf
    • https://cdn.shopify.com/s/files/1/0449/7837/2766/files/american_date_format.pdf
    • https://cdn.shopify.com/s/files/1/0433/6818/6024/files/pdf_antenna_construction.pdf
    • https://cdn.shopify.com/s/files/1/0446/6740/4451/files/tinuwijepujamosivibizetu.pdf
    • https://cdn.shopify.com/s/files/1/0434/0659/0104/files/laxivabotanatelubagu.pdf
    • https://cdn.shopify.com/s/files/1/0428/8305/5782/files/fenewa.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/libidurekatomanazavevufi.pdf
    • https://cdn.shopify.com/s/files/1/0434/6393/4109/files/97488128402.pdf
    • https://cdn.shopify.com/s/files/1/0437/6697/2577/files/fundamentals_of_organic_chemistry_mcmurry.pdf
    • https://cdn.shopify.com/s/files/1/0447/8651/6134/files/research_ontology.pdf
    • https://cdn.shopify.com/s/files/1/0440/7368/1061/files/88260664866.pdf
    • https://cdn.shopify.com/s/files/1/0429/9702/2871/files/86937272137.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_off00004874.bin
c3cd70b0edd525e4f013d050e55d90ea045466878ed5e057e443d470c07481f8
pdf-font-stream PDF embedded font (sfnt) at offset 0x4874 6048 bytes
font_01_sfnt_off00005d0d.bin
4396fa49ea4a1f8a95ba1a28be9c78faa0802ef66604578756f16de3a95c5a95
pdf-font-stream PDF embedded font (sfnt) at offset 0x5D0D 10120 bytes