Malicious PDF — malware analysis report

Static analysis result for SHA-256 db6597dee5928f7d…

MALICIOUS

PDF

42.0 KB Created: 2020-08-20 21:41:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f15317feec77d1d36bb049057f2e18c9 SHA-1: 17eccb384d2c7d5bcc9da6c157a4fd814c12ccef SHA-256: db6597dee5928f7dbf38f9c80f47ef827ed3d3341905337e832cfb0102741778
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains a mass external link farm, with a primary redirector URL pointing to a known malicious domain. The document body, though heavily obfuscated, contains the same lure text and URLs as observed in the heuristics. The ML classifier strongly indicates maliciousness. The primary attack vector appears to be directing users to malicious sites via embedded links.

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=british+council+big+numbers+worksheet
    • http://jirewar.wyevalleycrafts.com/uploads/1/3/0/8/130874540/pokudapixowonak.pdf
    • http://files.musicinmclean.org/uploads/1/3/0/7/130739037/vibepizilana.pdf
    • http://files.dassiedahan-author.com/uploads/1/3/1/4/131436971/wixodasa.pdf
    • http://files.mermaidsutra.net/uploads/1/3/1/6/131637814/a3d34add6105.pdf
    • https://cdn.shopify.com/s/files/1/0437/0127/2729/files/jinoxagaz.pdf
    • https://cdn.shopify.com/s/files/1/0431/8298/1278/files/bilingual_first_language_acquisition.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/nalekubaserigudopen.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/97897646990.pdf
    • https://cdn.shopify.com/s/files/1/0438/4430/5056/files/angulos_na_circunferencia_exercicios.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/kujefitil.pdf
    • https://cdn.shopify.com/s/files/1/0449/7866/7688/files/55791626838.pdf
    • https://cdn.shopify.com/s/files/1/0440/2964/0854/files/arquitectura_renacentista.pdf
    • https://cdn.shopify.com/s/files/1/0428/9521/2697/files/carpet_sweeper_reviews_consumer_reports.pdf
    • https://cdn.shopify.com/s/files/1/0435/5329/2440/files/19937039631.pdf
    • https://cdn.shopify.com/s/files/1/0433/2358/8773/files/32860269339.pdf
    • https://cdn.shopify.com/s/files/1/0440/4789/2630/files/antihistaminicos_en_el_embarazo.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_off0000641c.bin
37219508ddd6442023b83dcf08766699c9c01e3b049612ec6d4fc032c3339b38
pdf-font-stream PDF embedded font (sfnt) at offset 0x641C 5348 bytes
font_01_sfnt_off00007637.bin
aed6139dcd0f0f74db8d7368a9306bd604a2d3c341f901382e80852b1e9c4830
pdf-font-stream PDF embedded font (sfnt) at offset 0x7637 10616 bytes