Malicious PDF — malware analysis report

Static analysis result for SHA-256 f63550ebe7cd2712…

MALICIOUS

PDF

72.6 KB Created: 2021-04-10 08:55:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 52dded65da7bde8efc5ae93f917e066b SHA-1: 5b0e5aca2ab7d474bd67840ac4f5d88ae9f6c809 SHA-256: f63550ebe7cd27120082c0608afcf6a05ae22063104611da6446b05d27e8abd1
96 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 suspicious domains or are potentially malicious. The document body, though heavily obfuscated, suggests a lure related to 'USMLEworld biostatistics subject rev', likely an attempt to trick users into clicking on a malicious link disguised as educational material.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 4

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://ambrose.edu/sites/default/files/webform/zabufenopi.pdf
    • http://www.guninetwork.org/system/files/webform/heirri_proposals/44437875789.pdf
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/tekuxegejarikuferibo.pdf
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/5308316073.pdf
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/sumeli.pdf
    • http://spotlight-sites.com/sites/default/files/webform/jalipoxelelikepobolid.pdf
    • https://www.telluridescience.org/sites/default/files/tstc-applications/fezijorimofilafomifum.pdf
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/48103714077.pdf
    • https://www.a1touchsolution.nl/sites/default/files/87400145234.pdf
    • https://aboss.by/sites/default/files/webform/vobefoxejajizagosoberob.pdf
    • https://www.mainephilanthropy.org/sites/default/files/5296457674.pdf
    • https://www.telluridescience.org/sites/default/files/tstc-applications/kuvusuwube.pdf
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/fifomibap.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=usmleworld+biostatistics+subject+rev
    • https://community.princeton.edu/system/files/webform/xakefabobadu.pdf
    • https://www.healthdata.org/sites/default/files/resumes/53082175038.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d200.bin
96674f194964781a65a933089c003ee82dac001550cf3b1d58deef8dc34c5088
pdf-font-stream PDF embedded font (sfnt) at offset 0xD200 5220 bytes
font_01_sfnt_off0000e3da.bin
d00e227fe6188e3aa6b00db82deed9cd25fd27aff4e3ea31c28723b4383e02f2
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3DA 10260 bytes
font_02_sfnt_off000106de.bin
1062cd8ddf90f4344fa193b395386d5669df1a952e5759311ca261a71931f361
pdf-font-stream PDF embedded font (sfnt) at offset 0x106DE 4324 bytes