Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1d3f81e65cde5f5…

MALICIOUS

PDF

34.8 KB Created: 2020-08-12 06:22:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2b0b8f2cfcb0bb7477efbb76013f1748 SHA-1: 2f1bc7e154173c769f86de7dfa987b1e9ac3f14a SHA-256: b1d3f81e65cde5f5cf620bb4922cd734cbb6c714587f2fab1d0972a5d522face
154 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, which is also present in the document body. This link, 'https://ttraff.cc/wb?keyword=lector%20de%20pdf%20para%20windows%20xp', is designed to lure users by pretending to offer a PDF reader for Windows XP. The document also contains a large number of embedded links, many pointing to Shopify domains, which is indicative of a link farm used for SEO poisoning or distributing malicious content. The ML classifier also strongly flagged this PDF as malicious.

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/wb?keyword=lector%20de%20pdf%20para%20windows%20xp
    • http://files.ovmsso.org/uploads/1/3/2/6/132680860/lusuwodubetebofa.pdf
    • http://files.flancmanfrisch.com/uploads/1/3/1/8/131871414/widapabidazuz-vulomal-pepap.pdf
    • http://files.eastsidefamilytherapy.net/uploads/1/3/2/6/132681464/dazoraxu.pdf
    • https://cdn.shopify.com/s/files/1/0437/8161/9861/files/43442178230.pdf
    • https://cdn.shopify.com/s/files/1/0431/7177/4615/files/62063991475.pdf
    • https://cdn.shopify.com/s/files/1/0433/9446/5948/files/51040029782.pdf
    • https://cdn.shopify.com/s/files/1/0433/9718/5701/files/3_month_lsat_study_schedule.pdf
    • https://cdn.shopify.com/s/files/1/0439/4539/4331/files/historia_de_la_contabilidad_libros.pdf
    • https://cdn.shopify.com/s/files/1/0438/5370/9472/files/astragalus_literatura.pdf
    • https://cdn.shopify.com/s/files/1/0434/1687/9271/files/51896059988.pdf
    • https://cdn.shopify.com/s/files/1/0435/6587/5359/files/surgical_pathology_report.pdf
    • https://cdn.shopify.com/s/files/1/0430/6462/3265/files/bigujusowix.pdf
    • https://cdn.shopify.com/s/files/1/0430/7006/2754/files/28312292533.pdf
    • https://cdn.shopify.com/s/files/1/0434/5593/8725/files/cervical_lymphadenitis.pdf
    • https://cdn.shopify.com/s/files/1/0431/9494/1603/files/2789306758.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_off00004947.bin
ffd9bb963dbf18af6f897df4284792977f070267f850433b2950c42abc6d61f9
pdf-font-stream PDF embedded font (sfnt) at offset 0x4947 5216 bytes
font_01_sfnt_off00005b2c.bin
0ba52cb46974f2ac688cd6be2d7640e241a322bc8dca44eb4887e5c60aa0cdb4
pdf-font-stream PDF embedded font (sfnt) at offset 0x5B2C 10392 bytes