Malicious PDF — malware analysis report

Static analysis result for SHA-256 2a3f0b33fce15c01…

MALICIOUS

PDF

77.8 KB Created: 2021-04-07 00:48:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 3c5c0e83378e09bc362dfeb434de8d55 SHA-1: 4da4871d3b1b866304b3dbba1cb72b1608ea5006 SHA-256: 2a3f0b33fce15c01ac18f34f40194d5f91981799131777dadce1f747e6a1fe10
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to disposable domains, and is flagged as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document lures.

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://ambrose.edu/sites/default/files/webform/kubuxodadiwozubak.pdf In PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/paxifufal.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/xugapovapoz.pdfIn PDF document text
    • https://www.dgs-interparts.be/sites/default/files/41094691834.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/nufideleze.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/fenalop.pdfIn PDF document text
    • https://www.telluridescience.org/sites/default/files/tstc-applications/kuvusuwube.pdfIn PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/susumijifiwef.pdfIn PDF document text
    • https://www.newburghgroup.com/sites/default/files/webform/resumes/falaburisidibiwad.pdfIn PDF document text
    • https://www.blplegal.com/sites/default/files/webform/32112495638.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/68138040624.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/47116150145.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • http://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=asme+section+viii+div+1+pdf+downloadPDF link annotation
    • https://www.vub.be/sites/vub/files/webform/gegisikirusesikogibo.pdfIn PDF document text
    • https://ec.europa.eu/eip/agriculture/sites/default/files/webform/juvuwudonuvusenovirem.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e528.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE528 5184 bytes
SHA-256: 9c8bef0549ad14ac803bf0c9b9025506862be69aa4ca2722456f045ca08029c4
font_01_sfnt_off0000f6ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6CE 10984 bytes
SHA-256: 89b190450ba99f49fb35c0d4f5314ee9f81392086156d19a4ffd1351ee6bf653
font_02_sfnt_off00011c20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C20 4324 bytes
SHA-256: 7f6049e5011acf0e8581793f2bc2bb947aac2929fdb77abc318b2a6155c1ef71