Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf3f7f31d141c303…

MALICIOUS

PDF

53.1 KB Created: 2020-09-01 12:07:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2353d9afcb7a9e18c2ca478a6e818b41 SHA-1: 39b3471728977f6ed77ea6c282cec1144d9255e5 SHA-256: cf3f7f31d141c30350319a58fe5db481c97c52c45adad02268eaa7a2ed66e280
154 Risk Score

Malware Insights

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

The PDF file contains a significant number of embedded links, identified as a link farm. One of these links, 'https://ttraff.ru/wix?keyword=xamarin+forms+data+binding+converter', points to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains references to this URL, suggesting its primary purpose is to lure users to malicious sites. The ML classifier also strongly indicated maliciousness.

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=xamarin+forms+data+binding+converter
    • https://static.usrfiles.com/ugd/79cb75_f3709566ddfa4942a27ad4c5d98157b7.pdf
    • https://static.usrfiles.com/ugd/4d6844_711a4e542f40403bba7a3908dc5b6189.pdf
    • https://static.usrfiles.com/ugd/e3834b_48a7162239e44b06861a5bc336c865c9.pdf
    • https://static.usrfiles.com/ugd/b8c837_1afed4af97774fb89ac2cd30adfd8427.pdf
    • https://static.usrfiles.com/ugd/b8c837_483394ee66ae42fe82a0d3b3a35fe1b5.pdf
    • https://static.usrfiles.com/ugd/6240f8_f308f096dbea43a7af7bb5b77a0c33f4.pdf
    • https://static.usrfiles.com/ugd/b8c837_1e5cf08febb645f4a86526b1eacced81.pdf
    • https://static.usrfiles.com/ugd/086daf_d5f695d2024a462a96982e88ea617d4b.pdf
    • https://static.usrfiles.com/ugd/a4e402_a7c688631206459584eafba6ce84f905.pdf
    • https://static.usrfiles.com/ugd/078c79_4c110f7a7f114d5d8bad0b521a2b2e59.pdf
    • https://static.usrfiles.com/ugd/f55bec_3c931b3435b44e67a7b720776b091556.pdf
    • https://static.usrfiles.com/ugd/b8c837_35abd24c862d4319b7e29aed266c0f7d.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_off000077a8.bin
9400925aa980dafd6a1c7f149c4f9d55b66420795e5a70f2885e100dfe809ad8
pdf-font-stream PDF embedded font (sfnt) at offset 0x77A8 5276 bytes
font_01_sfnt_off0000897b.bin
6e6d73a78d1d1760376857957a429493f51080d22e17d6194e68f253ef07ff0a
pdf-font-stream PDF embedded font (sfnt) at offset 0x897B 15408 bytes
font_02_sfnt_off0000b9c9.bin
4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3
pdf-font-stream PDF embedded font (sfnt) at offset 0xB9C9 4324 bytes