Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d738fcac80eb382…

MALICIOUS

PDF

39.8 KB Created: 2020-08-24 06:48:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cdb685173f4c53318c6582fbe9a7bf5b SHA-1: e118b450f6fdbd0c66559d5b6da384538ee1920f SHA-256: 4d738fcac80eb382762515879e11bbacb89e5a560051d52665b4ec0a11763985
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded links, many of which point to external resources. One critical heuristic indicates that the PDF links to known malicious redirector infrastructure, specifically 'ttraff.com', which is used in conjunction with lures like 'ielts answer sheet listening'. The ML classifier also strongly flagged this PDF as malicious. The document body contains obfuscated text and URLs, further supporting the malicious intent of redirecting users to potentially harmful 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.com/pify?keyword=ielts+answer+sheet+listening
    • http://vusinozo.movingintune.com/uploads/1/3/1/4/131437254/8394781.pdf
    • http://files.dprservices513.com/uploads/1/3/0/8/130874163/mepil_mururaw.pdf
    • http://files.stephensandauphotography.com/uploads/1/3/1/4/131413550/70dcc2b8c97e.pdf
    • http://files.roadefc.com/uploads/1/3/1/3/131378990/6823487.pdf
    • https://cdn.shopify.com/s/files/1/0435/8314/4093/files/body_language_bangla_book.pdf
    • https://cdn.shopify.com/s/files/1/0428/6719/6063/files/40297880905.pdf
    • https://cdn.shopify.com/s/files/1/0434/1307/8174/files/79295192622.pdf
    • https://cdn.shopify.com/s/files/1/0433/6130/4727/files/86968801229.pdf
    • https://cdn.shopify.com/s/files/1/0434/5639/7464/files/nikiwej.pdf
    • https://cdn.shopify.com/s/files/1/0434/7982/6597/files/90261872499.pdf
    • https://cdn.shopify.com/s/files/1/0432/2741/4696/files/matrices_in_latex.pdf
    • https://cdn.shopify.com/s/files/1/0431/8789/6480/files/minecraft_1._12_windows_10.pdf
    • https://cdn.shopify.com/s/files/1/0459/9962/0263/files/railroad_tycoon_3_maps_free.pdf
    • https://cdn.shopify.com/s/files/1/0430/5495/6695/files/31539194031.pdf
    • https://cdn.shopify.com/s/files/1/0435/2750/4024/files/29065688602.pdf
    • https://cdn.shopify.com/s/files/1/0430/8038/4674/files/95911785653.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_off00005fcd.bin
f4ebc46b88446d058b4013054b257d9ffd20180132b9ca7baa45f459365e31df
pdf-font-stream PDF embedded font (sfnt) at offset 0x5FCD 4976 bytes
font_01_sfnt_off000070bc.bin
acbd835cf2fdf0c3fdf1c83a0d1ac7f552d4799907a312140631d04657eb7630
pdf-font-stream PDF embedded font (sfnt) at offset 0x70BC 9952 bytes