Malicious PDF — malware analysis report

Static analysis result for SHA-256 37890f5dc323bae8…

MALICIOUS

PDF

41.7 KB Created: 2020-08-30 17:56:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 050860ee3c036e697a7abda2a264f7f8 SHA-1: 6e456e1136749160b82cfacc0869fc4de175e555 SHA-256: 37890f5dc323bae87b43098dc95eb7cf2525cbdb34e49e8600924dd5a6f37023
150 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by multiple critical heuristics for containing malicious redirector links and a link farm. The ML classifier also strongly indicated maliciousness. The primary malicious IOC is the URL https://ttraff.com/wix?keyword=aprendiz+de+sabio+opiniones, which is part of a known malicious redirector infrastructure. The document body, though heavily obfuscated, contains this URL and numerous other links to static.usrfiles.com, suggesting a coordinated effort to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 3

  • 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.
  • 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=aprendiz+de+sabio+opiniones
    • https://static.usrfiles.com/ugd/b8c837_64705baa84e54f04aaef17b344e24764.pdf
    • https://static.usrfiles.com/ugd/912de2_e25951c634a34fbdbdd6d1b702bd2287.pdf
    • https://static.usrfiles.com/ugd/1e4819_e949e3e9e9ab4df8849205ded49cc384.pdf
    • https://static.usrfiles.com/ugd/913720_8d29fd6915c546d3aae9975a51a295e7.pdf
    • https://static.usrfiles.com/ugd/ea5d7b_3a22f3ebc22e453894389a5ab891d71d.pdf
    • https://static.usrfiles.com/ugd/f1d680_95889db1b18d4e0cbc57d4c45934af1d.pdf
    • https://static.usrfiles.com/ugd/b8c837_81432d7ddcb1452f9123bbef2aaf12b7.pdf
    • https://static.usrfiles.com/ugd/22739b_d9d8460d1ae5449fafb09616a23abc57.pdf
    • https://static.usrfiles.com/ugd/d5d855_b31531a11d9a4c8b946bbead01387d6a.pdf
    • https://static.usrfiles.com/ugd/80c1db_b0b655a6ba034041be0a7ed38748c8e3.pdf
    • https://static.usrfiles.com/ugd/b8c837_701b8985ac11465f8bac312c70df71e6.pdf
    • https://static.usrfiles.com/ugd/b8c837_84a0b93aa568496e8e1fa3454ffecf22.pdf
    • https://static.usrfiles.com/ugd/b11f6d_8534873d41234a3882d1d3b2fb8846a7.pdf
    • https://static.usrfiles.com/ugd/e73fea_f44c7d264ba24325984000249aeeddf5.pdf
    • https://static.usrfiles.com/ugd/b8c837_7f6d886286824ed19f172aa85ea21f3e.pdf
    • https://static.usrfiles.com/ugd/d5cf39_2261de272b1449499001a1020af536f9.pdf
    • https://static.usrfiles.com/ugd/b8c837_f81cc0d72986438190d1c685ee02e642.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
font_00_sfnt_off00004cbd.bin
11980816acc4b42456eed0ef8ada23c454fce7ac177a22fab5a3333fe4d78fd8
pdf-font-stream PDF embedded font (sfnt) at offset 0x4CBD 5100 bytes
font_01_sfnt_off00005e17.bin
2aaf816a611b6e79b9c3bf66280ea0a52082b8418dd58d2d13eb4c1dfd2c5ade
pdf-font-stream PDF embedded font (sfnt) at offset 0x5E17 11480 bytes
font_02_sfnt_off00008287.bin
5561c4d82fbfca81a66c04c36e059cfbf7b6188384656767d3368d526b1af784
pdf-font-stream PDF embedded font (sfnt) at offset 0x8287 16296 bytes