Malicious PDF — malware analysis report

Static analysis result for SHA-256 99f2f515d76ae8e5…

MALICIOUS

PDF

50.2 KB Created: 2020-08-30 08:52:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: edc29dec0664c6e51e8802c246cc13a5 SHA-1: f8bcaf22a60e8cfb8dddcd14b2097e5d5dd70677 SHA-256: 99f2f515d76ae8e5e91d210dae788640fc19a5782c19f8fd1b894c91f5dc3b21
152 Risk Score

Malware Insights

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

The PDF was flagged as malicious by a machine learning classifier and contains a link to a known malicious redirector. The redirector URL is 'https://ttraff.cc/wix?keyword=samurai+jack+art+style'. The document also contains a large number of external PDF links, many pointing to static.usrfiles.com, which is identified as a link farm. The presence of these links suggests an attempt to manipulate search engine results or distribute further 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.cc/wix?keyword=samurai+jack+art+style
    • https://static.usrfiles.com/ugd/96768c_81419e2de63e4fa4a79cad3ac4ebb89d.pdf
    • https://static.usrfiles.com/ugd/9e53d4_231ff080af5e488fa06f87d7dcdf9711.pdf
    • https://static.usrfiles.com/ugd/b8c837_7499261b048c48148410d7ed21b63506.pdf
    • https://static.usrfiles.com/ugd/b8c837_3743659eb6c8433fa757ec478e5318f0.pdf
    • https://static.usrfiles.com/ugd/c068f8_f283093d8e12417faef9892331e4074a.pdf
    • https://cdn.shopify.com/s/files/1/0428/2833/3212/files/python_interview_questions_for_freshers.pdf
    • https://cdn.shopify.com/s/files/1/0432/8872/3616/files/xosifutosupiniw.pdf
    • https://cdn.shopify.com/s/files/1/0427/8901/1612/files/lalovudinelena.pdf
    • https://cdn.shopify.com/s/files/1/0469/0444/3040/files/rusaziriz.pdf
    • https://static.usrfiles.com/ugd/b8c837_c4815c83b5ea43cca81076e6b930a981.pdf
    • https://static.usrfiles.com/ugd/b8c837_9ef5f099d7c24892b17015a034fc3c0e.pdf
    • https://static.usrfiles.com/ugd/b914b5_bd9415a0b83c4f9ca3dcefe012852c43.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off00009e90.bin
8a25fccc3c8fc3194ec1f675628be82a430fa962b9ad5ac76d05aabc030e0cc4
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x9E90 18544 bytes
font_00_sfnt_off000068c7.bin
3609a633435fb112e6654a0185c5e7270d94b8c53304b4a1bff03f884daa0d72
pdf-font-stream PDF embedded font (sfnt) at offset 0x68C7 5288 bytes
font_01_sfnt_off00007ab3.bin
8233e6f75308e47c827074098a41ff4697d05f0bdc19221d3a96cf9707a9d4c2
pdf-font-stream PDF embedded font (sfnt) at offset 0x7AB3 10572 bytes