Malicious PDF — malware analysis report

Static analysis result for SHA-256 a28c4f496c4e37df…

MALICIOUS

PDF

39.7 KB Created: 2020-10-12 00:13:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: efdee233783b55bb273b605ee193c48e SHA-1: 31070b7bcd2388045457a9de283e93f9e0a079d7 SHA-256: a28c4f496c4e37dfb75538ce2a3e65828d17c22fa65de6d7ed6865ae2ea4fdce
152 Risk Score

Malware Insights

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

The PDF file contains numerous embedded links, with a critical heuristic firing indicating it links to known malicious redirector infrastructure. Another critical heuristic identifies it as a PDF link farm, with many links pointing to external PDF files. The ML classifier also strongly flagged this PDF as malicious. The document body contains text related to 'Poesia 20 de noviembre' and includes the identified malicious URL, suggesting a lure or redirection mechanism.

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/strik?keyword=poesia+20+de+noviembre
    • http://files.theteachinglifestyle.com/uploads/1/3/0/7/130739198/c241caecda.pdf
    • http://files.studioofcreativity.com/uploads/1/3/1/6/131606502/7860484.pdf
    • http://paziga.dinki.me/uploads/1/3/2/6/132682701/pojifaj.pdf
    • http://files.morrisseauartist.com/uploads/1/3/0/7/130739769/kodofukikidir.pdf
    • http://files.utdgammas.com/uploads/1/3/1/3/131384432/2eff578803f4e.pdf
    • http://files.scholasticgrads.com/uploads/1/3/2/7/132710491/jidamipikiberu-begozaduwed.pdf
    • http://files.firstumcds.org/uploads/1/3/2/3/132303371/4969207.pdf
    • http://files.shopthcattire.com/uploads/1/3/0/8/130814169/93d4e5641036.pdf
    • https://cdn.shopify.com/s/files/1/0467/9722/6133/files/craigslist_ms_gulf_coast_cars.pdf
    • https://cdn.shopify.com/s/files/1/0428/6224/8095/files/saxon_math_6th_grade_answers.pdf
    • https://cdn.shopify.com/s/files/1/0435/5109/6993/files/muscle_rack_shelving_costco.pdf
    • https://cdn.shopify.com/s/files/1/0433/9898/7926/files/135426693.pdf
    • https://cdn.shopify.com/s/files/1/0430/5806/9655/files/55415238878.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_off000059c4.bin
4a8284e0c3be4a550bf3239c1050593ce4b98c83e13c3bdbe8e1d5bc1f9241e3
pdf-font-stream PDF embedded font (sfnt) at offset 0x59C4 5412 bytes
font_01_sfnt_off00006c11.bin
1f71866342339dee8e2db346fc14306ce86d01e81cbbae6634b294afc9a92f0f
pdf-font-stream PDF embedded font (sfnt) at offset 0x6C11 11492 bytes