Malicious PDF — malware analysis report

Static analysis result for SHA-256 a646deadc59aafab…

MALICIOUS

PDF

72.3 KB Created: 2021-04-21 03:19:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: 009641bb7420b7e5fe5b57074ca75811 SHA-1: 37f6480071a3ce165fcd36dc7327ee052511e66e SHA-256: a646deadc59aafab179120c66341d9e5ed9a3c3973fce7625e11943302599e97
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, indicating a high likelihood of malicious intent. The heuristic analysis identified it as a link farm on disposable hosting, with numerous embedded URLs pointing to various domains. While no scripts were explicitly extracted, the nature of the embedded URLs suggests an attempt to redirect users to potentially harmful sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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/degajakuko.pdf In PDF document text
    • https://ambrose.edu/sites/default/files/webform/48232920683.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/taxebuvokorutupimapo.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/26688185713.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/kepasibadugemefobovabo.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/GLLx1DTH0VQ/uplcv?utm_term=yamaha+moxf8+vs+modx8PDF link annotation
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/7842358922.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/90369837207.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/ludazerubadariwevulefaxu.pdfIn PDF document text
    • https://ec.europa.eu/eip/agriculture/sites/default/files/webform/44438097533.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/47045932069.pdfIn PDF document text
    • https://www.healthdata.org/sites/default/files/resumes/78922999772.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_off0000dc1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC1E 5300 bytes
SHA-256: b3bf4d24a68cafa025cf168854c38a5f536408604a9e38bbb78219e0fdc87504
font_01_sfnt_off0000ee12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE12 11408 bytes
SHA-256: 7f97bec6b72dec43cf9e0445232b2055b02fbb9dae9f0c500f3796d9a502d91f