Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bd083580edf087e…

MALICIOUS

PDF

32.8 KB Created: 2020-08-29 04:17:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 187c6afbf6fbcd160ffdfdc0477bc1a4 SHA-1: a97c4d21aaf2fb6084ba98398b783e12df9943de SHA-256: 8bd083580edf087e4e17053dd7a48d7935b389466e255c2ca899ac909df8d4b8
152 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to 'https://ttraff.ru/wix?keyword=read+noughts+and+crosses+online+free'. Additionally, it exhibits characteristics of a PDF link farm, with numerous embedded links, including one to 'https://cdn.shopify.com/s/files/1/0438/2644/6498/files/19181725611.pdf'. The ML classifier also flagged this PDF with high confidence. No scripts were extracted, and the document body was heavily obfuscated, making it difficult to determine the exact lure, but the presence of a malicious redirector is a strong indicator of malicious intent.

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=read+noughts+and+crosses+online+free
    • https://cdn.shopify.com/s/files/1/0438/2644/6498/files/19181725611.pdf
    • https://cdn.shopify.com/s/files/1/0461/7450/3065/files/bikuzik.pdf
    • https://cdn.shopify.com/s/files/1/0438/4066/7810/files/72456969283.pdf
    • https://cdn.shopify.com/s/files/1/0430/2022/2627/files/namavaxujefiwefexoruw.pdf
    • https://cdn.shopify.com/s/files/1/0429/4819/8556/files/gawozoremikexezuxabanaf.pdf
    • https://cdn.shopify.com/s/files/1/0427/9504/0924/files/91140541624.pdf
    • https://cdn.shopify.com/s/files/1/0431/0243/7527/files/primer_mp4_movie_download.pdf
    • https://static.usrfiles.com/ugd/b8c837_ffb9a4596e70430c8c666932c403267b.pdf
    • https://static.usrfiles.com/ugd/b8c837_f0f034a21b39484ca9803036e72f6feb.pdf
    • https://static.usrfiles.com/ugd/b8c837_d32996d0bfbd46f9bb88b303c60f149d.pdf
    • https://static.usrfiles.com/ugd/b8c837_136a7fb3610b45b89b3d2de77bad39f3.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_off00004364.bin
65d769e35bb9f4c205eb97f7ab8d5ba0802a92ba13cdf3aed6308dca3b2810f1
pdf-font-stream PDF embedded font (sfnt) at offset 0x4364 5288 bytes
font_01_sfnt_off0000555a.bin
e5e611222abd16e6dcedb0827b793df3dc51653d725b943e9e0e837a5f6a8630
pdf-font-stream PDF embedded font (sfnt) at offset 0x555A 9720 bytes