Malicious PDF — malware analysis report

Static analysis result for SHA-256 85b82603d74dc9dd…

MALICIOUS

PDF

63.2 KB Created: 2021-04-17 05:37:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: d9864350af2fb0928a90660ec2bfd151 SHA-1: f8930f2764333e6474ce9f9ee50458ee2ba91c0a SHA-256: 85b82603d74dc9dd47a5c1e4ac7ca28c5326d4be6289c61e99b743d6802dc4e2
126 Risk Score

Malware Insights

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

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable domains or are structured as link farms, indicating a likely attempt to redirect users to malicious sites. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, suggesting the document is designed to host a large number of links for SEO manipulation or to distribute malware.

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 http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/lozege.pdf In PDF document text
    • http://www.friendlycc.com/sites/default/files/webform/mitiporaju.pdfIn PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/tawapiseligimagawawujimo.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/tonitunivopevefasoxezaw.pdfIn PDF document text
    • https://extranet.blanchisserie-toulousaine-de-sante.com/sites/extranet.blanchisserie-toulousaine-de-sante.com/files/documents/justificatifs/bariwogutal.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/58994315224.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/28911573484.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/89737617204.pdfIn PDF document text
    • https://www.blplegal.com/sites/default/files/webform/25596831819.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/nukuromenalifaru.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/zMnd8XtcwSM/uplcv?utm_term=navien+nr+240a+flame+rod+assemblyPDF link annotation
    • https://lib.asu.edu/system/files/webform/46247033309.pdfIn PDF document text
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/33404153997.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_off0000baf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBAF8 5684 bytes
SHA-256: c3a7a17359a1d0775f45230b140d3618f7a30248f4308528d5f5695dd7493a54
font_01_sfnt_off0000ce55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE55 9932 bytes
SHA-256: 8fa209ca60eddd0afb6951878b6bcd3964f805d43970e8bfe40967e8b14dc550