Malicious PDF — malware analysis report

Static analysis result for SHA-256 92c8b5bf473bcfca…

MALICIOUS

PDF

82.9 KB Created: 2021-04-24 21:37:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: cbd304f773509cd446ea7dee847c8f80 SHA-1: 9dc0101e0b2d0112310edd7662ceb4e0d2483684 SHA-256: 92c8b5bf473bcfca4518ae3d2ff22facc60a0ea0f499dfe5fa4d09a47fd155af
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, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to unknown or potentially malicious domains, suggesting an attempt to redirect users to harmful sites. The PDF structure and the presence of external URIs indicate a link farm or phishing lure.

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.dgs-interparts.be/sites/default/files/bipaxuvimul.pdf In PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/72917344941.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/kupoxogij.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/ralivowu.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/pugixenarewowu.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/43963154407.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/zavemazawutojene.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/~3/3CAf4wW3hvY/uplcv?utm_term=husky+power+washer+change+nozzlePDF link annotation
    • https://www.vub.be/sites/vub/files/webform/86005813007.pdfIn PDF document text
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/37488496184.pdfIn PDF document text
    • https://umatter.princeton.edu/system/files/webform/requests/tutoturabawukaxubudevodor.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/21250884575.pdfIn PDF document text
    • https://drones.princeton.edu/system/files/webform/66931006591.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_off0001041c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1041C 5464 bytes
SHA-256: 5206b9b78a521b116c67d11f020c630f2048c48e1363fbb4899766bbad03898b
font_01_sfnt_off000116d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116D0 11832 bytes
SHA-256: 0801b455805ec56903c01cf53708765fe313ec9eb998f71378cff7ba6d3cb6b2