Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef74f1366e6fe7da…

MALICIOUS

PDF

40.3 KB Created: 2020-08-29 12:26:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d4a702c4733287ec5fce9e85bbf67fcf SHA-1: e17f095a8840df045103280b70553fe7d26a8f72 SHA-256: ef74f1366e6fe7da00c402a54d690f500c41a7a14e36f613ab5706f8a12237d2
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to Shopify domains hosting PDF files, suggesting a link farm or SEO poisoning tactic. One prominent link, 'https://ttraff.ru/wix?keyword=active+voice+to+passive+voice+exerci', is flagged as a malicious redirector. The document body, though heavily obfuscated, also contains this URL, indicating the primary intent is to lure the user to click on this malicious link. The ML classifier strongly supports the malicious nature of this PDF.

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=active+voice+to+passive+voice+exerci
    • https://cdn.shopify.com/s/files/1/0432/7076/6750/files/technical_analysis_for_dummies_book.pdf
    • https://cdn.shopify.com/s/files/1/0434/7409/2198/files/sujulitudidogav.pdf
    • https://cdn.shopify.com/s/files/1/0431/6502/4416/files/12398020722.pdf
    • https://cdn.shopify.com/s/files/1/0436/2685/6610/files/xewivigasuweforubelumupej.pdf
    • https://cdn.shopify.com/s/files/1/0462/6287/8359/files/85451949535.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/birizakidunupujudexi.pdf
    • https://cdn.shopify.com/s/files/1/0435/7157/6993/files/pancreas_anatomia_fisiologia.pdf
    • https://cdn.shopify.com/s/files/1/0431/6217/3604/files/59955207048.pdf
    • https://static.usrfiles.com/ugd/b8c837_7155f7c6b781428d89e675d6822e7004.pdf
    • https://static.usrfiles.com/ugd/b8c837_68d2c8855b2a4a2b8bc2f4f02c9fc655.pdf
    • https://static.usrfiles.com/ugd/b8c837_503930efaa134338ab701eb24487daf0.pdf
    • https://static.usrfiles.com/ugd/b8c837_9e75a66ee6744e128087b1a2a042d7f4.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_off000053f4.bin
623ae24eea11aad5d7e3d34339fd17d9c90d431222dd8cdc9e2a73e50ec3957b
pdf-font-stream PDF embedded font (sfnt) at offset 0x53F4 4696 bytes
font_01_sfnt_off000063f7.bin
be7e2448e82dd2fdb411db756625bb56455291364d6d7d72d6a9bb4f4239089a
pdf-font-stream PDF embedded font (sfnt) at offset 0x63F7 10164 bytes
font_02_sfnt_off00008699.bin
1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361
pdf-font-stream PDF embedded font (sfnt) at offset 0x8699 4324 bytes