Malicious PDF — malware analysis report

Static analysis result for SHA-256 841525d50c4ca923…

MALICIOUS

PDF

39.8 KB Created: 2020-08-02 08:05:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: a9ed4706e3e477a0d8b1832d00938885 SHA-1: d4f2b68e6d3c29a763e70a4ab93fec8f90cf2e85 SHA-256: 841525d50c4ca923c4e6e89f06398983ea2e5b90f4a631d9ea17087c4f114642
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many pointing to Shopify domains hosting other PDFs, and one critical link to a known malicious redirector. This suggests an attempt to create a link farm or SEO spam, potentially leading users to malicious content. The ML classifier also strongly indicated maliciousness.

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=tci+history+alive
    • http://files.royalmarketingconcepts.com/uploads/1/3/1/3/131380741/997332.pdf
    • http://files.horizonbrews.com/uploads/1/3/0/7/130775892/suminapu-subov-vugovebusasepew.pdf
    • http://files.doubleglazinggosport.co.uk/uploads/1/3/1/3/131383837/260b57a5671d.pdf
    • http://files.lifeandentertainment.com/uploads/1/3/2/6/132695329/4538649.pdf
    • http://files.vonkaltbach.com/uploads/1/3/0/7/130739535/3199060.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0431/3353/4357/files/nuzuvezenaxusidezu.pdf
    • https://cdn.shopify.com/s/files/1/0434/5397/2633/files/voxalipoke.pdf
    • https://cdn.shopify.com/s/files/1/0433/7552/6051/files/89609332464.pdf
    • https://cdn.shopify.com/s/files/1/0435/8370/1155/files/23264867480.pdf
    • https://cdn.shopify.com/s/files/1/0434/8179/2664/files/1072579971.pdf
    • https://cdn.shopify.com/s/files/1/0431/8383/3249/files/15779886045.pdf
    • https://cdn.shopify.com/s/files/1/0430/6134/6466/files/93146921690.pdf
    • https://cdn.shopify.com/s/files/1/0430/4830/4797/files/loselukifisek.pdf
    • https://cdn.shopify.com/s/files/1/0428/5313/8588/files/62177533120.pdf
    • https://cdn.shopify.com/s/files/1/0430/5187/6509/files/81283680533.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/30617095305.pdf
    • https://cdn.shopify.com/s/files/1/0436/8809/9993/files/sorry_ciara_lyric.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_off00005d81.bin
d6d067ed027e7da06cb4386cd89bb38006b7c5432b2d86c780cb3e8ad929f998
pdf-font-stream PDF embedded font (sfnt) at offset 0x5D81 5000 bytes
font_01_sfnt_off00006e89.bin
fb2f5d487eb58c1b40575b07db31e6b3c2bfed1162c9cd3e846cd01511e1cd6d
pdf-font-stream PDF embedded font (sfnt) at offset 0x6E89 10460 bytes