Malicious PDF — malware analysis report

Static analysis result for SHA-256 e83f9581606b0a52…

MALICIOUS

PDF

64.5 KB Created: 2020-08-11 17:03:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 23d31fe095c5ff22f3b6d50f3a100d9e SHA-1: bc70392b2e1210c5a7f579d7683e839ca262dcf4 SHA-256: e83f9581606b0a52fb3dfecba03845cbe778e4e03ae1810343a53b5959420252
154 Risk Score

Malware Insights

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

The PDF contains multiple embedded links, with one specifically pointing to a known malicious redirector. The ML classifier strongly indicates maliciousness. The document body, though heavily obfuscated, contains the URL that is also flagged by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. This suggests the primary goal is to redirect the user to malicious infrastructure.

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/wb?keyword=flip%20teaching%20pdf
    • http://files.stewartvillesportsmansclub.com/uploads/1/3/1/4/131453291/1eb6b5.pdf
    • http://files.daksart.com/uploads/1/3/1/4/131438461/jomeru.pdf
    • http://files.upaabc.org/uploads/1/3/0/7/130739678/6541203.pdf
    • http://fimil.congressweek.org/uploads/1/3/1/3/131380480/sanumisupa_selitikaxe_sokexod_vuxikoke.pdf
    • https://cdn.shopify.com/s/files/1/0431/0820/4708/files/velibiwud.pdf
    • https://cdn.shopify.com/s/files/1/0436/9793/0393/files/mann_whitney_u_test_python.pdf
    • https://cdn.shopify.com/s/files/1/0439/2452/1128/files/zizajufononazarugeviro.pdf
    • https://cdn.shopify.com/s/files/1/0432/3606/5438/files/kefapof.pdf
    • https://cdn.shopify.com/s/files/1/0433/6350/0197/files/wafulurutexizako.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/wuvinotagug.pdf
    • https://cdn.shopify.com/s/files/1/0432/2118/8763/files/metabolic_syndrome_review_article.pdf
    • https://cdn.shopify.com/s/files/1/0427/9474/6023/files/81780437688.pdf
    • https://cdn.shopify.com/s/files/1/0434/7455/0949/files/1461320059.pdf
    • https://cdn.shopify.com/s/files/1/0428/9229/6359/files/janib.pdf
    • https://cdn.shopify.com/s/files/1/0440/7197/7110/files/san_jose_state_campus_map.pdf
    • https://cdn.shopify.com/s/files/1/0437/1100/4821/files/76382153601.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_off0000bfe6.bin
46312ddd1097bfa671ae5d185ef884050985c1b7bcd2d02c40eeb31b123b37ea
pdf-font-stream PDF embedded font (sfnt) at offset 0xBFE6 5100 bytes
font_01_sfnt_off0000d138.bin
2652a7fe393c7547fac9dd58f8a97c1f0fefe1befe191446a4ea3eada1e0f9eb
pdf-font-stream PDF embedded font (sfnt) at offset 0xD138 10628 bytes