Malicious PDF — malware analysis report

Static analysis result for SHA-256 61b7539cab535992…

MALICIOUS

PDF

37.5 KB Created: 2020-08-11 20:48:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 402163c23663d8736ddd2752a6c812dc SHA-1: 37d8a332c080c96833a306991a7fee0cbb834517 SHA-256: 61b7539cab535992e399d1ca9df3948586ff72a07aa0fb53e1b97ed8d6b8c8a6
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links, many pointing to benign Shopify URLs, but one critical link directs to a known malicious redirector. The document body, though heavily obfuscated, contains text related to educational worksheets and also repeats the malicious URL, suggesting a lure to trick users into clicking it. The presence of embedded URLs and the ML classifier's high confidence indicate 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/wb?keyword=uniformly%20accelerated%20particle%20model%20worksheet%205%20quantitative%20acceleration%20problems
    • http://files.pinkpapayasblog.com/uploads/1/3/1/6/131606366/7205486.pdf
    • http://files.journeytolegacy.com/uploads/1/3/1/3/131379844/2809249.pdf
    • http://files.amodeosfarm.com/uploads/1/3/2/7/132712306/jitikew.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0430/0609/9605/files/yamaha_rx-_v675_manual.pdf
    • https://cdn.shopify.com/s/files/1/0437/8004/6997/files/50634177805.pdf
    • https://cdn.shopify.com/s/files/1/0432/9147/6133/files/binomio_de_newton.pdf
    • https://cdn.shopify.com/s/files/1/0430/5630/0186/files/boxizekimiduzovef.pdf
    • https://cdn.shopify.com/s/files/1/0428/8924/8924/files/audi_0-_60_times.pdf
    • https://cdn.shopify.com/s/files/1/0436/3019/8937/files/84960131288.pdf
    • https://cdn.shopify.com/s/files/1/0429/7441/2949/files/kozimukig.pdf
    • https://cdn.shopify.com/s/files/1/0435/5276/8151/files/vesaz.pdf
    • https://cdn.shopify.com/s/files/1/0433/7929/4358/files/vasiretelajunev.pdf
    • https://cdn.shopify.com/s/files/1/0434/5564/3813/files/social_aspects_of_development.pdf
    • https://cdn.shopify.com/s/files/1/0430/4135/7973/files/bopewotisovaf.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00004c5b.bin
9547eda78448ee97fe713d6edd23110bd1ca19de4f050252e2da1bac9e8f1702
pdf-font-stream PDF embedded font (sfnt) at offset 0x4C5B 6092 bytes
font_01_sfnt_off00006100.bin
c34b121c45e137a6da28da98b5295ba8b24b917e8cb8e5b2aa0cad69d0b31229
pdf-font-stream PDF embedded font (sfnt) at offset 0x6100 11944 bytes