Malicious PDF — malware analysis report

Static analysis result for SHA-256 88ecc97ec4f81803…

MALICIOUS

PDF

73.4 KB Created: 2021-04-06 22:13:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: ff936f731bdb823935f9aef51513855b SHA-1: 13146a9c4669818ca04882ece5f72a8cf1dd6c16 SHA-256: 88ecc97ec4f818034770825865feb38510b11303b7fd598f8eb11539475c3c83
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing or trojan. It contains numerous embedded URLs pointing to various domains, many of which appear to be part of a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggests the document's purpose is to manipulate search engine results or redirect users to potentially harmful content hosted across these domains.

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://architecturaldesigninc.com/sites/default/files/72694480293.pdf In PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/5308316073.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/90018929780.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/tirudekamevajoluzagobumi.pdfIn PDF document text
    • http://www.friendlycc.com/sites/default/files/webform/29579557159.pdfIn PDF document text
    • https://www.mainephilanthropy.org/sites/default/files/wimatetomowitiki.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/tojawi.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/87400145234.pdfIn PDF document text
    • https://web.liderpapel.com/sites/default/files/webform/dojoxopanikofogenag.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/buvonajevomowetizebijix.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/palepipob.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/7486912807.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/lomaxitafuvutatu.pdfIn PDF document text
    • https://www.newburghgroup.com/sites/default/files/webform/resumes/tikijoti.pdfIn PDF document text
    • https://www.dgs-interparts.be/sites/default/files/68462010443.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=benim+hocam+kpss+tarih+pdfPDF link annotation
    • https://thesanfordschool.asu.edu/sites/default/files/webform/fapivo.pdfIn PDF document text
    • https://thesanfordschool.asu.edu/sites/default/files/webform/xumigisapiwonatidokababup.pdfIn PDF document text
    • https://minorsoncampus.princeton.edu/system/files/webform/wetesagepe.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_off0000dd4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD4C 5476 bytes
SHA-256: 7728834dc927bb8e6484bbfcc7671acbe010548480838a2c2930a012c14bc2c1
font_01_sfnt_off0000efc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFC1 12376 bytes
SHA-256: 5b30376eeee47e0cccf7138da92b9d981f9144ed941d82700765f81c6da54d5e