Malicious PDF — malware analysis report

Static analysis result for SHA-256 5bf173938fd2e0bd…

MALICIOUS

PDF

53.0 KB Created: 2020-08-22 11:17:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: de02293a57ffd60ecaefb0725778d529 SHA-1: 19791fa53c91a9638d98bca725f5226324b580b8 SHA-256: 5bf173938fd2e0bdb430df3f5099a34c6c59858ea76bd20c5fff9eedf718a644
154 Risk Score

Malware Insights

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

The PDF contains numerous links to external resources, many of which are hosted on Shopify and appear to be part of a link farm. One critical heuristic identified a link to a known malicious redirector, ttraff.cc, which is likely used to obscure the final destination. The ML classifier also strongly indicated maliciousness. While no scripts were extracted, the presence of a malicious redirector and the link farm structure suggest an attempt to manipulate search rankings or distribute malicious content.

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=mean+median+mode+exercises+with+answers
    • http://files.lucygransbury.com.au/uploads/1/3/2/6/132680827/rasivefixavewuni.pdf
    • http://files.ahhousecleaning.com/uploads/1/3/1/4/131409200/wivobagukarawafisosa.pdf
    • http://files.innovativemhsolutions.com/uploads/1/3/0/7/130739919/ritubu_libunig.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0433/6628/5480/files/91749032807.pdf
    • https://cdn.shopify.com/s/files/1/0431/6453/2900/files/28922606491.pdf
    • https://cdn.shopify.com/s/files/1/0434/7923/6774/files/jenut.pdf
    • https://cdn.shopify.com/s/files/1/0435/5080/2081/files/step_by_step_bulgarian_language_and_culture_for_foreigners.pdf
    • https://cdn.shopify.com/s/files/1/0432/5192/5155/files/ludowevisisupijotizul.pdf
    • https://cdn.shopify.com/s/files/1/0437/5265/2951/files/oxford_dictionary_download.pdf
    • https://cdn.shopify.com/s/files/1/0428/1987/9068/files/11593953196.pdf
    • https://cdn.shopify.com/s/files/1/0437/4183/9511/files/brightsign_xt244.pdf
    • https://cdn.shopify.com/s/files/1/0433/9954/4984/files/20758480546.pdf
    • https://cdn.shopify.com/s/files/1/0433/4167/6694/files/vibujamaxogimigupini.pdf
    • https://cdn.shopify.com/s/files/1/0432/7417/4622/files/wuxewula.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_off0000888b.bin
53e633e5c3b70772e06b4685417abe9ca567ed1f4c570289c050bd077d5cb5cd
pdf-font-stream PDF embedded font (sfnt) at offset 0x888B 5312 bytes
font_01_sfnt_off00009a81.bin
a857ec281b6217a567ab6df4217a73b25d5dd88f6fbe2284b6621864f2174637
pdf-font-stream PDF embedded font (sfnt) at offset 0x9A81 14248 bytes