Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b8ce845c9dac8bb…

MALICIOUS

PDF

39.5 KB Created: 2020-08-16 23:42:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 961aa5be2e6f1f3e355059957ba43090 SHA-1: f7c7656ce2e1bbd27668f933cb9213dcdd2115be SHA-256: 5b8ce845c9dac8bb4af47d9663fe59de0cc672d0df306cc2c579501b2e951bc2
154 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.cc, which is presented as a "chopsticks easy piano music sheet" in the document body. This suggests a phishing or malware distribution lure. The PDF also hosts a large number of external links, many pointing to Shopify, which is indicative of a link farm used to obscure malicious intent. No scripts were extracted, but the presence of malicious links and the ML classifier's high confidence score support the malicious verdict.

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/pify?keyword=chopsticks+easy+piano+music+sheet
    • http://files.videoheads.co.uk/uploads/1/3/1/4/131408100/8c5dba02.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0429/0953/2316/files/bisiwukew.pdf
    • https://cdn.shopify.com/s/files/1/0428/5962/6655/files/circulatory_system_worksheet.pdf
    • https://cdn.shopify.com/s/files/1/0432/9163/9974/files/logical_reasoning_questions_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0430/2402/3715/files/99530557163.pdf
    • https://cdn.shopify.com/s/files/1/0432/5857/7046/files/vopaxir.pdf
    • https://cdn.shopify.com/s/files/1/0431/7341/3028/files/metejujajuba.pdf
    • https://cdn.shopify.com/s/files/1/0432/7941/7504/files/50341300217.pdf
    • https://cdn.shopify.com/s/files/1/0428/4999/2860/files/konejuwevekukawurolobi.pdf
    • https://cdn.shopify.com/s/files/1/0433/3905/5253/files/check_mark_alt_code.pdf
    • https://cdn.shopify.com/s/files/1/0440/7685/9557/files/altova_xmlspy_tutorial.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_off00005ebc.bin
bd782673c35f005048fd2643c0c5e9480f0ec218460cffb84bee3b33a6bd52e2
pdf-font-stream PDF embedded font (sfnt) at offset 0x5EBC 5116 bytes
font_01_sfnt_off00007001.bin
df98106816dcb79787f8707ca89a0a249b3c156b53b280ed22290c616ec7287e
pdf-font-stream PDF embedded font (sfnt) at offset 0x7001 9780 bytes