Malicious PDF — malware analysis report

Static analysis result for SHA-256 194578ac6164b1c5…

MALICIOUS

PDF

52.6 KB Created: 2020-08-17 00:26:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 61b59c4735a9d52d58810f9483f91ee9 SHA-1: 4d868674167b36ae35be5ef028b64df781037e69 SHA-256: 194578ac6164b1c5f1bb1899b0ac06dc68f3fee332680962d7e0820a4f54b290
154 Risk Score

Malware Insights

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

The PDF contains embedded links that redirect to malicious infrastructure, as indicated by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The document body, though heavily obfuscated, contains a string that appears to be a lure for educational content. The ML classifier strongly flagged this PDF as malicious. The primary IOC is the redirector URL, which is likely used to host or chain to further 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=macromolecules+worksheet+high+school+biology
    • http://fipoxise.securefire.co.uk/uploads/1/3/1/4/131438379/worezepasebu.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0429/9679/3503/files/793918870.pdf
    • https://cdn.shopify.com/s/files/1/0438/6127/8870/files/12135193431.pdf
    • https://cdn.shopify.com/s/files/1/0429/8178/5753/files/dufarusaledun.pdf
    • https://cdn.shopify.com/s/files/1/0432/3459/0878/files/siparegulagotopit.pdf
    • https://cdn.shopify.com/s/files/1/0435/2904/4119/files/libro_el_aprendiz_de_brujo_1_gratis.pdf
    • https://cdn.shopify.com/s/files/1/0433/6582/6719/files/all_company_logos_with_names.pdf
    • https://cdn.shopify.com/s/files/1/0447/1272/2585/files/wibegulijisilira.pdf
    • https://cdn.shopify.com/s/files/1/0428/5664/4774/files/rugemewubukojepozado.pdf
    • https://cdn.shopify.com/s/files/1/0437/3640/0037/files/87285904791.pdf
    • https://cdn.shopify.com/s/files/1/0430/8929/7568/files/bomeba.pdf
    • https://cdn.shopify.com/s/files/1/0430/9460/5975/files/disuzabezenenusuxelepukej.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_off00008d09.bin
3d477e286e7728acf62a3aa507436de7376345ee4162a7c256a9523fc25b71f3
pdf-font-stream PDF embedded font (sfnt) at offset 0x8D09 5616 bytes
font_01_sfnt_off0000a025.bin
46f1a04801d2eba7a5ad1e59453eaae4c64d71eaf7ca7e657732b16624933bfd
pdf-font-stream PDF embedded font (sfnt) at offset 0xA025 10928 bytes