Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7bb2a1b84c8cfba…

MALICIOUS

PDF

40.7 KB Created: 2020-08-30 10:26:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 18f361c7498145da7bcc256ab2114b38 SHA-1: 62d8d5c04bc99d3e079cca7fdfdaa79505de3f8e SHA-256: b7bb2a1b84c8cfba3b68d40884e101cbeb011314bc8875e818bb0441a82828ec
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, many of which point to a link farm designed for SEO manipulation. One critical heuristic identified a direct link to known malicious redirector infrastructure at 'https://ttraff.ru/wix?keyword=seven+years+piano+sheet+music+pdf'. The document body, though heavily obfuscated, appears to be a lure related to piano sheet music. The ML classifier strongly indicates 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.ru/wix?keyword=seven+years+piano+sheet+music+pdf
    • https://static.usrfiles.com/ugd/b8c837_a10dafd3932749539ba4508f2201c88d.pdf
    • https://static.usrfiles.com/ugd/b8c837_6336458b2b384417acd3f79f3e1a4aa3.pdf
    • https://static.usrfiles.com/ugd/f84671_3933173c693e4873b89740b7119c0b92.pdf
    • https://static.usrfiles.com/ugd/b8c837_4bf3d8c6071a45e3a927d926aac3c04e.pdf
    • https://cdn.shopify.com/s/files/1/0437/3001/0273/files/time_complexity_of_algorithms.pdf
    • https://cdn.shopify.com/s/files/1/0437/3394/2426/files/wopepumobuzir.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/26443777516.pdf
    • https://cdn.shopify.com/s/files/1/0429/7093/9541/files/13640899154.pdf
    • https://cdn.shopify.com/s/files/1/0430/3159/3113/files/zilavuso.pdf
    • https://cdn.shopify.com/s/files/1/0428/3629/5836/files/lakshmi_stotram.pdf
    • https://cdn.shopify.com/s/files/1/0463/0845/8661/files/29070891449.pdf
    • https://cdn.shopify.com/s/files/1/0440/8236/4566/files/lagapobelavidefuvakikuwut.pdf
    • https://cdn.shopify.com/s/files/1/0432/0785/2192/files/zitutituvezegelud.pdf
    • https://cdn.shopify.com/s/files/1/0429/6402/5493/files/acute_bronchitis_diagnosis.pdf
    • https://cdn.shopify.com/s/files/1/0438/0069/0848/files/fonozefukibozikalo.pdf
    • https://cdn.shopify.com/s/files/1/0432/5815/1072/files/iata_international_airport_codes.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_off00005255.bin
519aa31e2b78445415ef1b7f58f1448eed04f25e47237e9a97fc7249df731382
pdf-font-stream PDF embedded font (sfnt) at offset 0x5255 5628 bytes
font_01_sfnt_off00006557.bin
3e20b671fd4d59ad095e64e5a625b248e381748159537f89cb0b0a5a3a353e69
pdf-font-stream PDF embedded font (sfnt) at offset 0x6557 14844 bytes