Malicious PDF — malware analysis report

Static analysis result for SHA-256 13b275a430e9c805…

MALICIOUS

PDF

49.5 KB Created: 2020-07-31 10:37:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0a190339ef779a54e78fe01f7b883e12 SHA-1: bf8c6ae3e62e9abe8e3dc62a2cf44633882efbfb SHA-256: 13b275a430e9c805c78484f6f6326332ed8f1896c3b3c55dba063a63978b914a
154 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with one specifically pointing to a known malicious redirector. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, and the presence of many external PDF links suggests a link farm or SEO manipulation tactic to distribute malicious content.

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.com/pify?keyword=androgenos+y+estrogenos+pdf
    • http://files.drenzidesigns.com/uploads/1/3/0/7/130776529/191867dad0.pdf
    • http://files.phase2fitness.us/uploads/1/3/0/7/130775655/57025462.pdf
    • http://files.thelarsenflutestudio.com/uploads/1/3/0/8/130814902/tupas_mejirefoxa.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0435/0961/2712/files/gapez.pdf
    • https://cdn.shopify.com/s/files/1/0434/7399/3890/files/rapovevifuduwotakenubobik.pdf
    • https://cdn.shopify.com/s/files/1/0432/0421/4942/files/zabutere.pdf
    • https://cdn.shopify.com/s/files/1/0431/7003/7917/files/39116226844.pdf
    • https://cdn.shopify.com/s/files/1/0433/1339/7924/files/55851916306.pdf
    • https://cdn.shopify.com/s/files/1/0432/4111/1707/files/pewunufaweputo.pdf
    • https://cdn.shopify.com/s/files/1/0430/6799/8359/files/ravijiwewedimowoxo.pdf
    • https://cdn.shopify.com/s/files/1/0436/4356/8278/files/82866338259.pdf
    • https://cdn.shopify.com/s/files/1/0432/2790/6206/files/92674661261.pdf
    • https://cdn.shopify.com/s/files/1/0428/3046/3142/files/dezupipe.pdf
    • https://cdn.shopify.com/s/files/1/0432/0142/9662/files/39405997328.pdf
    • https://cdn.shopify.com/s/files/1/0428/0942/6079/files/xuwenime.pdf
    • https://cdn.shopify.com/s/files/1/0428/6555/7671/files/xumonosugugivulonemige.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_off00008186.bin
12b68ad58d0b12256d48690c6b114221887a9498bc8d67f222a661605e270d12
pdf-font-stream PDF embedded font (sfnt) at offset 0x8186 4800 bytes
font_01_sfnt_off000091e8.bin
c7aee439b9d4b194109b8b30de58abf5a3cbe0c60bcaf483a7531466e14d6334
pdf-font-stream PDF embedded font (sfnt) at offset 0x91E8 11532 bytes