Malicious PDF — malware analysis report

Static analysis result for SHA-256 6348a2d56c73b844…

MALICIOUS

PDF

71.2 KB Created: 2021-04-26 20:25:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 9d710b6c0f070c9d34869724c1020420 SHA-1: da96cbdab4143b90d092e6a4ebb3909380d8e2c4 SHA-256: 6348a2d56c73b8446e6cc5d98fe575661d52da75fedc0461437a1b7e641a0e1e
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to potentially malicious domains or are part of a link farm. The document body, though heavily obfuscated, suggests a lure related to 'home heating systems', which is a common tactic for phishing or malware distribution. No scripts were extracted, but the PDF structure and URL analysis strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 https://aboss.by/sites/default/files/webform/89266631471.pdf In PDF document text
    • http://portal-mysigma.com/system/files/student-proof/47432021317.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/56601188302.pdfIn PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/gurolaxi.pdfIn PDF document text
    • https://www.termis.org/system/files/webform/98565071062.pdfIn PDF document text
    • http://pilgrimland.com/sites/default/files/webform/resume-uploads/jokefogebefuzifuzew.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/65047245793.pdfIn PDF document text
    • http://www.pacificsportfraservalley.com/sites/default/files/webform/12938533755.pdfIn PDF document text
    • https://www.blplegal.com/sites/default/files/webform/54305505708.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/40110328039.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/BkSY9tpko7c/uplcv?utm_term=how+to+troubleshoot+home+heating+systemsPDF link annotation
    • https://printandmail.princeton.edu/system/files/webform/fasulegok.pdfIn PDF document text
    • https://gradfutures.princeton.edu/system/files/webform/49692556615.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_off0000db22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB22 5396 bytes
SHA-256: d03ada10a396d4adab0b998cc122b837b35d78bbb59fb574db33df60ab330941
font_01_sfnt_off0000ed60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED60 10080 bytes
SHA-256: 389c7e0a4ab607357801d16057666795c146e362a1a743748b7a950fee168072