Malicious PDF — malware analysis report

Static analysis result for SHA-256 25572babe024915d…

MALICIOUS

PDF

78.8 KB Created: 2021-04-20 21:09:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 9303761c66807af4ef7e83c9bc2d4213 SHA-1: d4787a9903860e81f1ad8cccd3baa87f2382f292 SHA-256: 25572babe024915db7234216a825e937272cc2d7016397223565d4dc7a089b5e
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 presence of numerous embedded URLs, many pointing to seemingly unrelated domains and employing UTM parameters, suggests a link farm or phishing lure designed to redirect users. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards a malicious document, likely used as a spearphishing attachment to distribute further payloads or phish for information.

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://www.cdcplumbing.com/sites/default/files/webform/contact-us/65589142167.pdf In PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/15691680518.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/59680287402.pdfIn PDF document text
    • https://www.termis.org/system/files/webform/manejuwavujegajejumoxak.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/32675510575.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/tuwagamutavuvefofufeniz.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/23528315583.pdfIn PDF document text
    • https://natsihwa.org.au/sites/default/files/webform/80931084074.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/wozupidojenebimovom.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/68038126183.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/ngfLrbzwjls/uplcv?utm_term=universal+methods+of+design+pdf+downloadPDF link annotation
    • https://campusrec.princeton.edu/system/files/webform/xapedejezorim.pdfIn PDF document text
    • https://ec.europa.eu/eip/agriculture/sites/default/files/webform/77241298986.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/13590028771.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_off0000f7b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7B8 5600 bytes
SHA-256: a8479c2a8c1f7fff3966fefeb3ebd9294a939a8265981a65ed16e4e17ed610cf
font_01_sfnt_off00010ab1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AB1 10572 bytes
SHA-256: 795b88a3eb336cc0c7ce6d4c35bdd3e5037bf9a89e5fa1a5860af2466656b01f