Malicious PDF — malware analysis report

Static analysis result for SHA-256 c45cf10baeb4638e…

MALICIOUS

PDF

76.7 KB Created: 2021-04-17 08:07:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 1ef154febc0f52a86e43a02203729ad6 SHA-1: fdfa4e3b6f3f30382db13423005f22cc29ddeefa SHA-256: c45cf10baeb4638e991f3e632726c20bec0d0381f08d50ff91f86c69d486841b
126 Risk Score

Malware Insights

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

The PDF sample was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to potentially disposable domains or are part of a link farm, a common tactic for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and numerous external links suggest it's designed to redirect users to malicious sites.

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://www.guninetwork.org/system/files/webform/heirri_proposals/rarapenebeku.pdf In PDF document text
    • https://www.termis.org/system/files/webform/manejuwavujegajejumoxak.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/kepasibadugemefobovabo.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/90018929780.pdfIn PDF document text
    • http://portal-mysigma.com/system/files/student-proof/woximinel.pdfIn PDF document text
    • https://www.dgs-interparts.be/sites/default/files/xufatonapa.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/buvonajevomowetizebijix.pdfIn PDF document text
    • https://www.jts.org.jo/sites/default/files/webform/76938035167.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/bekam.pdfIn PDF document text
    • https://www.jsif.org/sites/default/files/webform/kedoruxanagavapiwo.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/powevalixerofewum.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/72789215659.pdfIn PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/gurolaxi.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/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=fios+white+router+yellow+lightPDF link annotation
    • https://minorsoncampus.princeton.edu/system/files/webform/janoruzafasolefixos.pdfIn PDF document text
    • https://thesanfordschool.asu.edu/sites/default/files/webform/83703622856.pdfIn PDF document text
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/woragirewun.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/gegisikirusesikogibo.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/46247033309.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/rutepirunumobapof.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_off0000ef5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF5E 4884 bytes
SHA-256: 5beb63d89594d73cf1c6c957aa238abf675f08e31884701f9e1810dd3a83a197
font_01_sfnt_off0001000e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1000E 10632 bytes
SHA-256: e7a1d2b71b6e30d174ade895bd11790fe91db24cbce4dbb0c1f4f50fbbc61acb