Malicious PDF — malware analysis report

Static analysis result for SHA-256 6748dd318deb35d3…

MALICIOUS

PDF

36.8 KB Created: 2020-08-10 15:34:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 6368a31591a73e6d874fa8b132dd930f SHA-1: c3bb9268fcd6c8a12b9030451f8357b405c4b926 SHA-256: 6748dd318deb35d38c79e560c746a9c5638dcae68e82764fdd50544b3e2ba2f3
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to external PDF files, suggesting an attempt at SEO manipulation or a link farm. One critical heuristic identified a link to known malicious redirector infrastructure, specifically 'https://ttraff.cc/pify?keyword=arquitectura+sostenible+pdf+libros'. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains references to the same malicious URL, reinforcing the finding.

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=arquitectura+sostenible+pdf+libros
    • http://fulib.stmatthiasminocqua.com/uploads/1/3/1/6/131637016/70463f3da4f6b9a.pdf
    • http://files.philipkemp.com.au/uploads/1/3/1/3/131379680/5574036.pdf
    • http://files.nelsoneyewear.com/uploads/1/3/1/3/131379485/puwuxazapesetafakezi.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0437/2715/9445/files/bed_making_procedure.pdf
    • https://cdn.shopify.com/s/files/1/0430/0436/2906/files/maxuzadibopije.pdf
    • https://cdn.shopify.com/s/files/1/0430/6511/4775/files/8744991134.pdf
    • https://cdn.shopify.com/s/files/1/0438/4263/3890/files/lozukesidenavu.pdf
    • https://cdn.shopify.com/s/files/1/0434/9575/1842/files/62004300942.pdf
    • https://cdn.shopify.com/s/files/1/0429/6572/9429/files/dinove.pdf
    • https://cdn.shopify.com/s/files/1/0428/6310/0070/files/aptitude_formulas_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0432/7863/1072/files/gelotojobudurowiluxoboxow.pdf
    • https://cdn.shopify.com/s/files/1/0429/1959/2102/files/32919153162.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_off00004df9.bin
30b60f92ba78ec5e29d6bf17a74d88659a9e2ea9b86c44659f88a9c161c97f52
pdf-font-stream PDF embedded font (sfnt) at offset 0x4DF9 5404 bytes
font_01_sfnt_off00006059.bin
7ac50187ca010f2b976649a92e0846b0081f600aa5b4ef30e68f3d32d5c07bf1
pdf-font-stream PDF embedded font (sfnt) at offset 0x6059 11636 bytes