Malicious PDF — malware analysis report

Static analysis result for SHA-256 df702e2d9159cfe9…

MALICIOUS

PDF

68.3 KB Created: 2021-04-09 03:52:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 3b6986d5f19c4022c9c288841a2757ee SHA-1: b5de834f0370d34ba92617ab329c32f784e021a3 SHA-256: df702e2d9159cfe97b5d36f58599cca455b869116a9b145d1ccfdd73519dc717
126 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristic analysis revealed a link farm pattern with numerous embedded URLs, suggesting a phishing or malware distribution attempt. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a spearphishing attachment designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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 https://natsihwa.org.au/sites/default/files/webform/kixeje.pdf In PDF document text
    • http://seiary.com/sites/default/files/webform/rec/kutovaduro.pdfIn PDF document text
    • https://www.woonsocketri.org/system/temporary/webform/51053607868.pdfIn PDF document text
    • https://web.liderpapel.com/sites/default/files/webform/36759883892.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/30199048500.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/vewamilobofesiwukor.pdfIn PDF document text
    • https://www.newburghgroup.com/sites/default/files/webform/resumes/woxofenobe.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/jowodudarazobipadumalo.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/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=antimanuel+d%2527+%25C3%25A9conomie+bernard+maris+pdfPDF link annotation
    • https://campusrec.princeton.edu/system/files/webform/jelozubunumi.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/xapedejezorim.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_off0000c913.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC913 5608 bytes
SHA-256: af4594ff9cbd272722fba72622e2522d1236e8dc57e808a11cf0c130a0a183da
font_01_sfnt_off0000dbc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBC0 12332 bytes
SHA-256: 704fc7360de570ba7758c851c83665dec1e591cc23980532f42a412c2ee5141f