Malicious PDF — malware analysis report

Static analysis result for SHA-256 b20b255d350d7c91…

MALICIOUS

PDF

111.8 KB Created: 2021-04-15 03:30:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: dfbdb77e3a163b60fc43df1c92864a31 SHA-1: e34f32edfb1c2e9c81d0524b26cee7d48a142595 SHA-256: b20b255d350d7c911f7bc23a4ffbd8c3ef9ef450b2a01915f5356b08be379ea0
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, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable domains or are part of a link farm, indicating a likely attempt to direct users to malicious sites. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, suggesting the document is designed to artificially inflate search engine rankings or distribute links. No scripts were extracted, but the overall structure and heuristics point to a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.pacificsportfraservalley.com/sites/default/files/webform/pulipalukegibivep.pdf In PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/vonasajevevedatenalezeb.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/bemefunojupupik.pdfIn PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/45910982832.pdfIn PDF document text
    • http://www.pacificsportfraservalley.com/sites/default/files/webform/newusagolepilukakatukus.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/78191676466.pdfIn PDF document text
    • https://web.liderpapel.com/sites/default/files/webform/wavunivuzabanovomid.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/bulurifabisiwotubavigivos.pdfIn PDF document text
    • https://www.pharoxglobal.com/sites/default/files/webform/6669476875.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/70037852461.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/YTWXjIUwRh0/uplcv?utm_term=mamiya+rb67+pro+sd+motorized+backPDF link annotation
    • https://printandmail.princeton.edu/system/files/webform/54002061309.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/setokan.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/lijulur.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_off0001779e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1779E 5780 bytes
SHA-256: 65c35f201cb36b02ce244c965b35c082426a2ec11bb242303b268b9633bd70ad
font_01_sfnt_off00018b58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18B58 11676 bytes
SHA-256: 9a9eb68c065debee791e9bd022b282f63302e77cb735fb56a2cc17ad3adca392