Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd71e8372543ce0f…

MALICIOUS

PDF

75.8 KB Created: 2021-04-24 19:35:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: abe02e84c30d74e265a678f4b872b865 SHA-1: ac636a4fc99cd836ee0a608cf93cb1105831629c SHA-256: cd71e8372543ce0f9f03bb97b4e3116e4129b51b98390f03798a3fbe99d8dc26
126 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable or unknown domains, suggesting a link farm designed to redirect users to malicious content. The document body, though heavily obfuscated, appears to be a lure related to appliance repair, a common tactic for phishing.

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://www.blplegal.com/sites/default/files/webform/54305505708.pdf In PDF document text
    • https://www.dgs-interparts.be/sites/default/files/muvok.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/15194676649.pdfIn PDF document text
    • https://natsihwa.org.au/sites/default/files/webform/80931084074.pdfIn PDF document text
    • http://seiary.com/sites/default/files/webform/rec/netugapufuzutazegiwiwivi.pdfIn PDF document text
    • https://architecturaldesigninc.com/sites/default/files/vudezuluxi.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/buvonajevomowetizebijix.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/25680057182.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/22559513310.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/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=how+to+open+top+of+whirlpool+cabrio+dryerPDF link annotation
    • https://www.vub.be/sites/vub/files/webform/16824703900.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/16616798570.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/liwubuwivak.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/pagilavamuvawasaxega.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/40347257249.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_off0000ec1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC1D 5360 bytes
SHA-256: f1dfce9f16a457fb8b275c156fd5f2acff35ad449fee2ade4e9ddbee01c83820
font_01_sfnt_off0000fe63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE63 10588 bytes
SHA-256: 2dacddb0f70e90a8d2bf521e9ad19813bf05798db1349431ffeff09e2c941f4a