Malicious PDF — malware analysis report

Static analysis result for SHA-256 328b91da765d9d3c…

MALICIOUS

PDF

44.1 KB Created: 2020-07-07 12:14:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-15
MD5: c6d4068ada077d87a16fbff0e859e778 SHA-1: 4298c3ed93ca81ce83f6fe46066bf224dd601320 SHA-256: 328b91da765d9d3cabef009d11a1491fffecd9462114917a1b45843eb2735d6a
184 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 PDF files hosted on various domains, suggesting a link farm or SEO poisoning tactic. One prominent link directs to a known malicious redirector, indicating a phishing or malware distribution attempt. The document body, though partially corrupted, contains keywords related to the embedded links and a URL, reinforcing the lure.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.cc/wb?keyword=tratamiento%20candidiasis%20oral%20ni%C3%B1os%20pdf#tratamiento+candidiasis+oral+ni%25C3%25B1os+pdf In PDF document text
    • http://files.sgionet.com/uploads/1/3/0/8/130874413/zujojunejiguwimurob.pdfIn PDF document text
    • http://files.labcharter-pto.com/uploads/1/3/1/3/131379434/4b32ad6.pdfIn PDF document text
    • http://files.msrcampbell.com/uploads/1/3/1/8/131857193/lidumox-vujopobevezuj-dugosolizuxa.pdfIn PDF document text
    • http://files.gbyws.org/uploads/1/3/1/4/131483019/paludizixi-pazibokadelok-xovubonavegazuz-nobuxudisapefod.pdfIn PDF document text
    • http://files.explorestanton.com/uploads/1/3/1/4/131453216/6741733.pdfIn PDF document text
    • http://files.accountinguci.com/uploads/1/3/0/8/130873907/wafizelov-josekijaze.pdfIn PDF document text
    • http://files.mcmjanitorial.com/uploads/1/3/1/4/131406356/5b2cce2e6e7ba.pdfIn PDF document text
    • http://files.proyecto1867.com/uploads/1/3/2/3/132302913/mozolejemi-vexiramiga-leselu.pdfIn PDF document text
    • http://files.camera1.ca/uploads/1/3/1/3/131380413/pizixejawij.pdfIn PDF document text
    • http://files.pennjournalconlaw.com/uploads/1/3/2/6/132682694/bawibixijuzawo.pdfIn PDF document text
    • http://files.agathafashion.shop/uploads/1/3/0/9/130969375/9654079.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://wikibasaruk.files.wordpress.com/2020/07/junuruf.pdfIn PDF document text
    • https://wenopunufata.files.wordpress.com/2020/06/bimajomekamom.pdfIn PDF document text
    • https://satipukaza.files.wordpress.com/2020/06/57539986619.pdfIn PDF document text
    • https://nubudin.files.wordpress.com/2020/06/69969951708.pdfIn PDF document text
    • https://dezulav.files.wordpress.com/2020/06/96133262241.pdfIn PDF document text
    • https://zijolaraf.files.wordpress.com/2020/06/xabexis.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006be2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6BE2 5252 bytes
SHA-256: dd66da111f2789fbfcdb28ab92987f85bcf141582fcd061b614f522b7df5a790
font_01_sfnt_off00007d55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7D55 10544 bytes
SHA-256: 2420c441f732b3be477a1a6d00352154d7c8bcc2c6fcc1263e7cda97d853fb50