Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a8fb71d2491161e…

MALICIOUS

PDF

36.1 KB Created: 2020-08-29 02:40:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8ac2bc527993ef9f32a35ca2b6b30272 SHA-1: fbad2a8f022a70cd51837a191f3d291279c7943a SHA-256: 7a8fb71d2491161e81c8679bf687f6e900de371a972d1f4be5a63fe5a7717641
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded links, many of which point to a link farm designed to artificially boost search engine rankings. One prominent link, 'https://ttraff.cc/wix?keyword=acupressure+books+free+download', is flagged as a malicious redirector. The document body, though heavily obfuscated, contains this URL and other PDF links, suggesting a social engineering attempt to drive traffic to potentially malicious sites.

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=acupressure+books+free+download
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/b8c837_a74e255dcd2b4b539ed13d5452bb075e.pdf
    • https://static.usrfiles.com/ugd/b8c837_61bd09aa55164e8187b767f01e3b8b5b.pdf
    • https://static.usrfiles.com/ugd/b8c837_971f29d3ee174c45a3ab1ecd491cf847.pdf
    • https://static.usrfiles.com/ugd/b8c837_e4b7d39b72a64b3a9ebd791606d268f6.pdf
    • https://cdn.shopify.com/s/files/1/0464/6289/4248/files/88567220845.pdf
    • https://cdn.shopify.com/s/files/1/0432/5765/9547/files/precalculus_with_limits_4th_edition.pdf
    • https://cdn.shopify.com/s/files/1/0434/0557/4311/files/samsung_android_phone_upto_5000.pdf
    • https://static.usrfiles.com/ugd/b8c837_36333086043b4e07be6b7cde5fc459aa.pdf
    • https://static.usrfiles.com/ugd/b8c837_ac1f4fb9224c400290d49ce88d731478.pdf
    • https://static.usrfiles.com/ugd/b8c837_c9f18cad06e041a6baedb4428c042c3d.pdf
    • https://static.usrfiles.com/ugd/b8c837_b644774a7460409fb246c2c0605552bb.pdf
    • https://static.usrfiles.com/ugd/b8c837_45f7ed31920c4654a82a8a0a1d4fe854.pdf
    • https://static.usrfiles.com/ugd/b8c837_f2b0b735e20c4f308f2f9922363ccce6.pdf
    • https://static.usrfiles.com/ugd/b8c837_5b2e3296347541adbc8f1a04cf718a93.pdf
    • https://static.usrfiles.com/ugd/b8c837_60789c81462d4bb8a0df1d37f5782e56.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00004e87.bin
d3a37282bd326ca9df0ed2a49380328e6e3ec77e271039bb5ef506c20f0dec05
pdf-font-stream PDF embedded font (sfnt) at offset 0x4E87 5432 bytes
font_01_sfnt_off0000611c.bin
d6dc165ae1be4fe8a285bf56b3222f0ed11519e01568bfd0285cab5ffec1ff6b
pdf-font-stream PDF embedded font (sfnt) at offset 0x611C 10116 bytes