Malicious PDF — malware analysis report

Static analysis result for SHA-256 11eae080eb9d1b4f…

MALICIOUS

PDF

68.1 KB Created: 2021-04-15 18:05:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: 5c18f134035d0c42083bbc425c6dd9d4 SHA-1: 9e8aeeeab56be06277ccb1f85ceaeee9c3825fb1 SHA-256: 11eae080eb9d1b4f4d8b1207340819192570bd93d2b5c5e7e0b5f8f899044f3f
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm on disposable hosting, with numerous embedded URLs pointing to potentially malicious domains. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest an attempt to lure users to external sites, likely for credential harvesting or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://cicatsalud.com/html/sites/default/files/webform/25507329945.pdf In PDF document text
    • http://www.guninetwork.org/system/files/webform/heirri_proposals/32710798707.pdfIn PDF document text
    • https://www.dgs-interparts.be/sites/default/files/viwiredozilopuvotudulufez.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/sinuwoxifazuroli.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/28695523124.pdfIn PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/tawapiseligimagawawujimo.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/53132673180.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/gurasijam.pdfIn PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/1289321409.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/juremetepatofuf.pdfIn PDF document text
    • https://www.dgs-interparts.be/sites/default/files/55949953827.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/14219433733.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/kanuvanirarotugawabu.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/LPIa9PGmDLg/uplcv?utm_term=intex+pool+filter+pump+leaking+from+topPDF link annotation
    • https://community.princeton.edu/system/files/webform/26098210740.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/tivajojisepizoni.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/tujuxegagisezemesolut.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_off0000d1c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1C2 5112 bytes
SHA-256: e0e7610c66ec49cc66655d1f95ead580ab591a995bc1aa172573533507a5db31
font_01_sfnt_off0000e317.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE317 9532 bytes
SHA-256: 0b15036d1a52967e8249dff6a1b271eb730b22e74b46b0dba6ba31acd661d08b