Malicious PDF — malware analysis report

Static analysis result for SHA-256 b90bd1d378322247…

MALICIOUS

PDF

68.9 KB Created: 2020-08-29 21:47:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 24004fe536588c9b74a9c0e223fcb812 SHA-1: 76e51dfc18ba0593e76ab557610624f0ae21e604 SHA-256: b90bd1d378322247548930a097db9af51dff757e15efdea7e5d32aa846e1a3ac
154 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links, many of which point to a redirector service. The document body, though heavily obfuscated, contains a URL that appears to be part of a link farm designed to drive traffic to malicious sites. The ML classifier strongly indicates maliciousness, and the PDF_MALICIOUS_REDIRECTOR_LINK heuristic confirms the presence of links to known malicious infrastructure.

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.link/wix?keyword=summer+high+heights+episode+1
    • https://static.usrfiles.com/ugd/b8c837_8afa378f9c414a4cad1c4fd2df8203d2.pdf
    • https://static.usrfiles.com/ugd/90423f_f714cc27f5c74a508fef17c62fe3e6cf.pdf
    • https://static.usrfiles.com/ugd/b8c837_1aa57594e02e441ea95b5da593fdcb4f.pdf
    • https://static.usrfiles.com/ugd/b8c837_d0a240b999dd4962a9aaa97d70bbd310.pdf
    • https://static.usrfiles.com/ugd/b8c837_b857d160b8a548139d7d13d2f8368409.pdf
    • https://static.usrfiles.com/ugd/1e4819_e949e3e9e9ab4df8849205ded49cc384.pdf
    • https://static.usrfiles.com/ugd/b8c837_eb337cc5f30340fc93be43de54c95934.pdf
    • https://static.usrfiles.com/ugd/b8c837_56a55d44d62a4731ad5ed01b4f256b52.pdf
    • https://static.usrfiles.com/ugd/b8c837_702f50131bac4d9f877ced03cde7340f.pdf
    • https://static.usrfiles.com/ugd/b8c837_471ef8e33f964ebba8d3aa96f8b02e83.pdf
    • https://static.usrfiles.com/ugd/097bd5_2b0b5c39ae82491495e461ab97409f59.pdf
    • https://static.usrfiles.com/ugd/271e65_4fe3922c24b445f3b81b4c6feb9dcae9.pdf
    • https://static.usrfiles.com/ugd/b50c55_181a6a83bd49458f8b775e54ddf79f56.pdf
    • https://static.usrfiles.com/ugd/238140_b9648dbdf2e746a9b3b77b0a7570417c.pdf
    • https://static.usrfiles.com/ugd/b8c837_f23478dd962a49229d888a6a32ad5557.pdf
    • https://static.usrfiles.com/ugd/b8c837_16c9052c15134492a2dc290baec472fc.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_off0000d165.bin
f4863859a8d8b28756df951edf58fcf663e81ad79b298feb5dbb274772fb3110
pdf-font-stream PDF embedded font (sfnt) at offset 0xD165 5288 bytes
font_01_sfnt_off0000e341.bin
8fe1b6f6f89ef994c9cb8965f73641253ae81d6c65984ce9fd559e81b5f3b204
pdf-font-stream PDF embedded font (sfnt) at offset 0xE341 10272 bytes