Malicious PDF — malware analysis report

Static analysis result for SHA-256 51fce439522ed840…

MALICIOUS

PDF

42.0 KB Created: 2020-08-10 23:58:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 201896951bc5871d7c76c6511373f32e SHA-1: eef04f0da2a0afb87b95ef53aab74b4a65766c08 SHA-256: 51fce439522ed84026d6affd658ef8bc58a47dfb43d5c1c2988095a114f87680
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to a link farm hosted on Shopify. One of the primary links directs to a known malicious redirector. The document body, though heavily obfuscated, contains the URL 'https://ttraff.ru/pify?keyword=capitalization+punctuation+worksheets+pdf', indicating a lure to external malicious content. The ML classifier 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.ru/pify?keyword=capitalization+punctuation+worksheets+pdf
    • http://files.crossfit6sblog.com/uploads/1/3/1/4/131438180/6767082.pdf
    • http://dabimobu.pringleimages.com/uploads/1/3/2/7/132740405/3360639.pdf
    • http://files.whisperwindaussies.com/uploads/1/3/1/3/131383247/5cd026c8b.pdf
    • https://cdn.shopify.com/s/files/1/0435/8150/5695/files/celulas_caliciformes_funcion.pdf
    • https://cdn.shopify.com/s/files/1/0430/4447/0945/files/tudixotuxelatovidivo.pdf
    • https://cdn.shopify.com/s/files/1/0434/5639/7464/files/xulomigozunixijedewaf.pdf
    • https://cdn.shopify.com/s/files/1/0432/0333/0209/files/62083017636.pdf
    • https://cdn.shopify.com/s/files/1/0429/1769/1559/files/89973078879.pdf
    • https://cdn.shopify.com/s/files/1/0431/4447/8874/files/rebigozuloke.pdf
    • https://cdn.shopify.com/s/files/1/0434/5734/7749/files/kimixikatasofekujinifit.pdf
    • https://cdn.shopify.com/s/files/1/0437/3184/5271/files/muzijebafovitag.pdf
    • https://cdn.shopify.com/s/files/1/0431/6689/2191/files/70760575000.pdf
    • https://cdn.shopify.com/s/files/1/0429/6169/8969/files/mevuwumogozurasejizusi.pdf
    • https://cdn.shopify.com/s/files/1/0435/4444/5082/files/pogasegeduloxekukidajub.pdf
    • https://cdn.shopify.com/s/files/1/0431/9143/5422/files/84068558347.pdf
    • https://cdn.shopify.com/s/files/1/0436/0408/2851/files/bironusuzok.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_off0000668f.bin
25add6ebc424bdda827f1b222210f2cdf2100f8cf406e4a8bd2d51aff45cc77b
pdf-font-stream PDF embedded font (sfnt) at offset 0x668F 5352 bytes
font_01_sfnt_off000078d3.bin
fd4242b0a36e31cf1d49186f0a89483d247e79b8ed2ad83e88b0b07de11d11f8
pdf-font-stream PDF embedded font (sfnt) at offset 0x78D3 9952 bytes