Malicious PDF — malware analysis report

Static analysis result for SHA-256 131d3c0bdb1f9f81…

MALICIOUS

PDF

67.2 KB Created: 2021-04-17 21:38:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: 727c606e67217b9e085371c44e5ac8d6 SHA-1: 0ad816630b73071a389645dc819216ca0f43e3df SHA-256: 131d3c0bdb1f9f8148ba0d0165599fb2c2645cf760b0e00cdbe3c3102402dd71
126 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to unknown or potentially malicious domains, suggesting a phishing or credential harvesting attempt. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it is designed to redirect users to external 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 https://www.ofalloncasting.com/sites/default/files/webform/gegemapoxazokex.pdf In PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/larigujumikanezazezogiwi.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/70037852461.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/49109440539.pdfIn PDF document text
    • https://www.cdcplumbing.com/sites/default/files/webform/contact-us/65589142167.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/bofuwidesuxugebogaxa.pdfIn PDF document text
    • https://aboss.by/sites/default/files/webform/76513539396.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/S30rS-6n6vg/uplcv?utm_term=what+is+firmament+in+the+biblePDF link annotation
    • https://printandmail.princeton.edu/system/files/webform/85064040694.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/53252105934.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/47045932069.pdfIn PDF document text
    • https://minorsoncampus.princeton.edu/system/files/webform/fujixedapilevunagujos.pdfIn PDF document text
    • https://drones.princeton.edu/system/files/webform/janewif.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_off0000ca1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA1B 5160 bytes
SHA-256: 6eb062eb2f7b54ec68aad40a4f83986be1dff3b8f05c0f1db9d971c8c13a385d
font_01_sfnt_off0000db89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB89 10840 bytes
SHA-256: 390ede992c0ad03655dcbfe02fd2496a4f07bd9d3037ef7a3feed208b588e618