Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f949be66b078477…

MALICIOUS

PDF

47.2 KB Created: 2020-08-31 03:38:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cb10c6673e8cbdcb07eb3ac3f77b5d19 SHA-1: 64dc48b95990ed3c93d3803db9b01afc2882d7a1 SHA-256: 8f949be66b078477ea05b098de6513302b29bfcf825d8a331bbc99e39a81da46
152 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by an ML classifier and contains a critical heuristic indicating it links to known malicious redirector infrastructure. The document body, though obfuscated, contains a URL that matches the malicious redirector. Additionally, the PDF contains a large number of embedded links to external PDF files, many hosted on static.usrfiles.com, suggesting a link farm or redirection strategy.

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=the+evil+within+tatiana
    • https://static.usrfiles.com/ugd/685707_3a283c95943e491097093e6ad0237b5a.pdf
    • https://static.usrfiles.com/ugd/b8c837_66982b67d4c2464abc877d2469cd7e2e.pdf
    • https://static.usrfiles.com/ugd/e3325f_f7c9e71b12ba4c49ab4b7bae63c6cbef.pdf
    • https://static.usrfiles.com/ugd/39cb9d_94656317b3d64a1b819b8e860ebdc46b.pdf
    • https://static.usrfiles.com/ugd/804ff6_64466a9947a446bcb76e2c54b6906202.pdf
    • https://static.usrfiles.com/ugd/850f07_389abd7ae6da4ca8b098153c7fdc91ef.pdf
    • https://static.usrfiles.com/ugd/b8c837_a817384f4a3c4bf39c1c9ee3421b6721.pdf
    • https://static.usrfiles.com/ugd/b8c837_7e4e60300a364766892853ec9bd7eabb.pdf
    • https://static.usrfiles.com/ugd/90423f_6b4956e2ad894e629054d381108c5b4b.pdf
    • https://static.usrfiles.com/ugd/8127dd_619932a7f48949f8b6b9ba1d0f9c11b8.pdf
    • https://static.usrfiles.com/ugd/b8c837_2118bb7747e146ccbc5113a3c7f1e372.pdf
    • https://static.usrfiles.com/ugd/b8c837_274c44d837e4401d9b06677bc2433ca2.pdf
    • https://static.usrfiles.com/ugd/2c608b_21192dc3581447b99d0a4e9e265ea8c4.pdf
    • https://cdn.shopify.com/s/files/1/0450/6674/8056/files/amalgam_dental_fillings.pdf
    • https://cdn.shopify.com/s/files/1/0437/2342/3912/files/guitar_chords_tamil_songs.pdf
    • https://cdn.shopify.com/s/files/1/0433/7922/8833/files/nelejuvefofinunidozenebev.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_off00007560.bin
0057225986a422213d78bd9e9128e080a553cdc48bd6d000c3335bb4b689c615
pdf-font-stream PDF embedded font (sfnt) at offset 0x7560 4600 bytes
font_01_sfnt_off00008519.bin
b42254530b3e77a7a58af53d28b9e0d4abff39474f164dc29fec5667e9f29706
pdf-font-stream PDF embedded font (sfnt) at offset 0x8519 13500 bytes