Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1a51a898a78b5d0…

MALICIOUS

PDF

43.4 KB Created: 2020-07-09 04:07:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-08-25
MD5: 9b6c78498e4fc0350acf1eedb856a254 SHA-1: 803e5886805f265af7795ac24f94401fc1ebc3a2 SHA-256: f1a51a898a78b5d0d4c40daa7bcf503335bbeae4920ddc24f1342baa81126c6c
184 Risk Score

Malware Insights

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

The PDF contains numerous links to external sites, masquerading as educational content to entice clicks. The heuristic PDF_MALICIOUS_REDIRECTOR_LINK indicates that at least one of these links directs to known malicious infrastructure. The ML classifier also strongly flagged this PDF as malicious. No scripts were extracted from this sample.

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=math%20worksheets%20free%206th%20grade In PDF document text
    • http://files.newleaforganizingllc.com/uploads/1/3/1/8/131857071/6418065.pdfIn PDF document text
    • http://files.beeffoundation.org/uploads/1/3/1/6/131637034/dadigaguxa.pdfIn PDF document text
    • http://files.mariecharpentier.net/uploads/1/3/1/4/131483019/batipaxadas.pdfIn PDF document text
    • http://files.pemmensgolf.net/uploads/1/3/1/3/131379612/febokibilodirina.pdfIn PDF document text
    • http://files.graham-enniskillen.com/uploads/1/3/1/4/131437172/nofupafa.pdfIn PDF document text
    • http://files.dogoodstore.net/uploads/1/3/0/7/130776249/vibubokisexan.pdfIn PDF document text
    • http://files.kimkirch.com/uploads/1/3/0/7/130775827/welobozutudirol-fulunim.pdfIn PDF document text
    • http://files.lightningridgerealestate.com.au/uploads/1/3/2/8/132815961/tuwor.pdfIn PDF document text
    • http://files.williamsburgrec.com/uploads/1/3/2/6/132682745/tagogumolizim_fofuzipupi.pdfIn PDF document text
    • http://files.bucketoblood.com/uploads/1/3/1/4/131438808/junix_ninani.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://zaneraji.files.wordpress.com/2020/07/bazemev.pdfIn PDF document text
    • https://litilazer.files.wordpress.com/2020/07/37186721005.pdfIn PDF document text
    • https://vedaduleguxi.files.wordpress.com/2020/07/23511417127.pdfIn PDF document text
    • https://mugitemos.files.wordpress.com/2020/06/jezofowajezetisodarujomak.pdfIn PDF document text
    • https://kevumex.files.wordpress.com/2020/06/likozafofojeriliwemawozo.pdfIn PDF document text
    • https://rilusepo.files.wordpress.com/2020/06/86010426678.pdfIn PDF document text
    • https://xonumef.files.wordpress.com/2020/07/50123152834.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/gowavofopinesifaremoka.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/61259485886.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/zugazad.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/11783771814.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_off00006c78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6C78 5088 bytes
SHA-256: 583c04fb8a3699340df50d5d058d8a6eeb8bc8545b444fc805862219c4e69cfc
font_01_sfnt_off00007df4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7DF4 10160 bytes
SHA-256: 2226a6b86c5f5bd6ed4993048a9b24a33f48cfce88ccb0ea44d22f2baefbd5c2