Malicious PDF — malware analysis report

Static analysis result for SHA-256 f7cae02b3640d7b8…

MALICIOUS

PDF

95.5 KB Created: 2021-04-10 00:43:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 73d84ad860e53d6848729500d82c05a0 SHA-1: 6a1115f3c3d989b4f769174bec8c457172996161 SHA-256: f7cae02b3640d7b81d5d3dd4af39f903d40cb039baad0257495a76fcb755ccf8
124 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. The document contains a link farm with numerous URLs, many of which are hosted on educational or organizational domains, likely to appear legitimate. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a tactic to obscure malicious intent through a large number of links on disposable hosting. No scripts were extracted, but the overall structure suggests a phishing lure for credentials or a download of further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7259

Heuristics 4

  • 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
  • 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://ambrose.edu/sites/default/files/webform/rebunedirewe.pdf In PDF document text
    • https://architecturaldesigninc.com/sites/default/files/vudezuluxi.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/23528315583.pdfIn PDF document text
    • http://www.guninetwork.org/system/files/webform/heirri_proposals/32710798707.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/nakevatekiviva.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/14219433733.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/95941620813.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/BvfzZFkJO3s/uplcv?utm_term=wacom+cintiq+driver+updatePDF link annotation
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/jonigumeneritid.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/luzixuganigofifabeja.pdfIn PDF document text
    • https://ec.europa.eu/eip/agriculture/sites/default/files/webform/66140853426.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/tivajojisepizoni.pdfIn PDF document text
    • https://www.healthdata.org/sites/default/files/resumes/18848190838.pdfIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000141ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x141ED 4000 bytes
SHA-256: 42ea7df2bf48a4c98d87af6871583030b26ab362d1b411de3b75c6e18b33446f
font_01_sfnt_off0001502c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1502C 5208 bytes
SHA-256: e9064349d6584be7e8281b62ea901d1393ca6b341bbb9cba7647dda1d3bb855e
font_02_sfnt_off000161d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x161D4 6288 bytes
SHA-256: 2f5bb4ef909d68fa185d99303ce452d11acd96d50b4c3c7265f444d185bb14e2