Malicious PDF — malware analysis report

Static analysis result for SHA-256 39cb1811ff20fd39…

MALICIOUS

PDF

34.0 KB Created: 2020-11-02 20:55:08 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2b99ff3aecf256c9b376cb1edec9b689 SHA-1: 1d340c0cee6bb991c1bb2e60e6cfd201c703abc2 SHA-256: 39cb1811ff20fd394e1befa43dce38ec294b6fbc15b7c5818d032b4c0851a414
154 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with a critical heuristic firing indicating a redirector to known malicious infrastructure. The document body, though heavily obfuscated, contains URLs that are part of a link farm, suggesting an attempt to manipulate search engine results or lure users to malicious sites. The ML classifier strongly indicates malicious intent.

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://cctraff.ru/123?keyword=vocabulary+workshop+unit+13+answers
    • https://xijoxamapapi.weebly.com/uploads/1/3/4/3/134337958/zokalij_nofudewedow_nevok.pdf
    • https://cdn-cms.f-static.net/uploads/4365575/normal_5f9238034cfee.pdf
    • https://pesajupamobe.weebly.com/uploads/1/3/1/6/131607203/busenijikabemu_xijepo_fapirofakuduv.pdf
    • https://kebakiwaranug.weebly.com/uploads/1/3/4/3/134317860/0e5329440.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/tiduro/energy_flow_in_aquatic_ecosystem.pdf
    • https://s3.amazonaws.com/kakef/clear_glass_ornaments_to_fill.pdf
    • https://s3.amazonaws.com/suxiweke/bitter_kola_health_benefits.pdf
    • https://s3.amazonaws.com/jovekus/jojasupaxadofoxixem.pdf
    • https://s3.amazonaws.com/bisegilupuf/stoichiometry_practice_mole-mass_answers.pdf
    • https://s3.amazonaws.com/wixanarer/amorphous_silicon_solar_cell.pdf
    • https://cdn.shopify.com/s/files/1/0434/6321/3209/files/mirarutidakarojivafuk.pdf
    • https://cdn.shopify.com/s/files/1/0485/3632/2203/files/gta_3_android_cheats.pdf
    • https://s3.amazonaws.com/wofaxil/is_google_email_down.pdf
    • https://s3.amazonaws.com/vavapekadoliti/5_branches_of_philosophy.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_off000048f7.bin
594e67df1b518b400185056a56233a183d785e20807d977313889c8a259f5249
pdf-font-stream PDF embedded font (sfnt) at offset 0x48F7 5600 bytes
font_01_sfnt_off00005c1d.bin
8280a14fd0889b1ba079c542af860335985e1cb3fffdd1f9988016d3f968a5c8
pdf-font-stream PDF embedded font (sfnt) at offset 0x5C1D 9188 bytes