Malicious PDF — malware analysis report

Static analysis result for SHA-256 24f6a5c0276f5cbe…

MALICIOUS

PDF

42.5 KB Created: 2020-08-29 02:33:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f6a09c2acc9f077bc170bcb3faf54aec SHA-1: ed543ed0da34772ed8f51d543f2a460878964996 SHA-256: 24f6a5c0276f5cbe3002805fdc94261ef4bb84cff76503d6ccdb0051e8802e83
152 Risk Score

Malware Insights

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

The PDF contains a link farm and a critical heuristic firing for a malicious redirector. The embedded URL, 'https://ttraff.com/wix?keyword=program+do+czytania+pdf+na+komputerz', is designed to trick users into downloading a malicious program by posing as a PDF reader. The ML classifier strongly indicates maliciousness, and the presence of numerous Shopify links suggests a tactic to obscure the malicious redirector.

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/wix?keyword=program+do+czytania+pdf+na+komputerz
    • https://cdn.shopify.com/s/files/1/0437/6592/3992/files/7305046560.pdf
    • https://cdn.shopify.com/s/files/1/0432/9714/4990/files/kirexi.pdf
    • https://cdn.shopify.com/s/files/1/0431/3248/5793/files/git_reset_commit.pdf
    • https://cdn.shopify.com/s/files/1/0447/5689/3847/files/82512453347.pdf
    • https://cdn.shopify.com/s/files/1/0432/0926/1217/files/caballo_de_troya_8_descarga_gratis.pdf
    • https://cdn.shopify.com/s/files/1/0434/1684/6488/files/49443718058.pdf
    • https://cdn.shopify.com/s/files/1/0430/2703/8369/files/30751302285.pdf
    • https://cdn.shopify.com/s/files/1/0431/8344/0030/files/24563780373.pdf
    • https://cdn.shopify.com/s/files/1/0437/2476/7400/files/35569056196.pdf
    • https://static.usrfiles.com/ugd/b8c837_fa7970f8d3f5486ba68204eadbf8bc0c.pdf
    • https://static.usrfiles.com/ugd/b8c837_f71dee7c754c49a1b475d2b705e2bff9.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/
    • https://cdn.shopify.com/s/files/1/0431/8344/0030/files/24563780373

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006476.bin
b9be961c49431d700f54022cfc31b3ad530cf732645835e0db37448785d0090e
pdf-font-stream PDF embedded font (sfnt) at offset 0x6476 5480 bytes
font_01_sfnt_off00007717.bin
27ae02604d7267cfc1420a7bfc24b64e5252c5e2d7890b28758e737aea61cf0f
pdf-font-stream PDF embedded font (sfnt) at offset 0x7717 11412 bytes