Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a6e806424c77e5f…

MALICIOUS

PDF

54.7 KB Created: 2020-08-30 16:52:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d1bca9c00eb5e6d04169dc21040aa78c SHA-1: 2a3dc00d78b37919e7612c09e69be06dbc13f59c SHA-256: 8a6e806424c77e5f256f2b7553432cbcd73104fceb86323b71618bbabf88f0f1
152 Risk Score

Malware Insights

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

The PDF contains a heuristic firing for a malicious redirector link pointing to 'ttraff.ru', which is used in conjunction with a keyword suggesting a software download lure. The document body, though heavily obfuscated, also contains this URL and references to 'Crystal disk info download'. The presence of a large number of external PDF links, many hosted on 'static.usrfiles.com', indicates a link farm designed to distribute traffic or host 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.ru/wix?keyword=crystal+disk+info+download
    • https://static.usrfiles.com/ugd/ef7b09_80a8655d1b9e4273a300c857fb83cbe4.pdf
    • https://static.usrfiles.com/ugd/defdb4_4bdf7af4ec144310bf9832860d984710.pdf
    • https://static.usrfiles.com/ugd/b8c837_317bc0550ebd4c2b950a42dea582c972.pdf
    • https://static.usrfiles.com/ugd/df4650_c627b4b6390a4ffb84112266f3c2e3d2.pdf
    • https://static.usrfiles.com/ugd/d5d855_d47970a82d8042bebe85a62c1435c260.pdf
    • https://static.usrfiles.com/ugd/41a0b6_30d0b1327057429e853b94eb355e9fe8.pdf
    • https://static.usrfiles.com/ugd/96768c_188358738e494dac80474788ee9ef241.pdf
    • https://static.usrfiles.com/ugd/b8c837_01d9be52db3f48eb85dce203f68a2ad5.pdf
    • https://static.usrfiles.com/ugd/2e4eb4_85f79c1aa13f436f9f986696dadb8072.pdf
    • https://static.usrfiles.com/ugd/0df15e_d3ca61b334094c38bbb265940f3637ad.pdf
    • https://static.usrfiles.com/ugd/b8c837_9f64b48ba92745fcb58da6a16f35c53d.pdf
    • https://static.usrfiles.com/ugd/b8c837_99d81550f2d043c0ae25a9aa20ca5d12.pdf
    • https://static.usrfiles.com/ugd/b8c837_aa6cf3ac9bec41c99a191e674a947401.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_off000099c2.bin
728ae2aebb0cd39e9639bbd27f51ddc3484911b62f33c96fa8d92c6112424af6
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x99C2 27920 bytes
font_00_sfnt_off00006624.bin
4cabead3caff75dcd2429af9ab5260db71cf7a9fe7d1ae2c4ee9fb82447b29e0
pdf-font-stream PDF embedded font (sfnt) at offset 0x6624 5064 bytes
font_01_sfnt_off00007784.bin
076791a5dd5fe66fa34c2bd3503abdbce8efc37ab6bfd2cbae711f518600b21c
pdf-font-stream PDF embedded font (sfnt) at offset 0x7784 9944 bytes