Malicious PDF — malware analysis report

Static analysis result for SHA-256 c9bb190937a1b91c…

MALICIOUS

PDF

100.7 KB Created: 2021-04-11 23:21:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: bcc1d927fe2adbadd0d444ba84a956ce SHA-1: 50643a4e5a176f87687a0f6d62e0f3f1a1c35bc5 SHA-256: c9bb190937a1b91c314ba70676716b1935ed1be9a760152e5d60a4a723b25339
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous external URIs pointing to various domains, some of which are marked as unknown reputation. Although no scripts were explicitly extracted, the PDF structure and the presence of external links suggest an attempt to redirect the user to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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 http://pilgrimland.com/sites/default/files/webform/resume-uploads/61975266633.pdf In PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/zizepuniket.pdfIn PDF document text
    • https://vectorcorp.net/sites/default/files/webform/resume/sowasipaxezok.pdfIn PDF document text
    • http://www.birdlifebotswana.org.bw/sites/default/files/webform/sightings-sketches/43600748611.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/78191676466.pdfIn PDF document text
    • http://russian-ice-spb.ru/sites/default/files/webform/files/69309865186.pdfIn PDF document text
    • https://www.telluridescience.org/sites/default/files/tstc-applications/90077644064.pdfIn PDF document text
    • https://web.liderpapel.com/sites/default/files/webform/kivalin.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=steven+universe+latino+temporada+6PDF link annotation
    • https://community.princeton.edu/system/files/webform/boranewibutafale.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/22535495660.pdfIn PDF document text
    • https://drones.princeton.edu/system/files/webform/xakunowegetudirojevogejiw.pdfIn PDF document text
    • https://ec.europa.eu/eip/agriculture/sites/default/files/webform/27560642257.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/pagilavamuvawasaxega.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/xakefabobadu.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_off00014b32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14B32 5420 bytes
SHA-256: 2f4d00ac2d2e9991509bbda679d9ddc129c93eaa53cac62c437cc54015750d30
font_01_sfnt_off00015d8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15D8D 12104 bytes
SHA-256: 2f741940a96ff3075d87c6cafb4650e45c4664e02badffbe1b87baf4f6ad9aee