Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f30a52fc193b2c7…

MALICIOUS

PDF

79.9 KB Created: 2021-04-21 15:57:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-17
MD5: 0912966d37b638c56a5b822658802e9b SHA-1: 6f57a598cdedb729f29551a7dd1b824969a7009b SHA-256: 3f30a52fc193b2c749c431fff9780e555955fc84d7c452a31bbed4fe781b9390
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 of which point to disposable domains or are structured as link farms, suggesting an attempt to redirect users to malicious sites. The document body, though heavily obfuscated, appears to be a lure related to physics, likely to trick users into clicking the embedded links.

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://ambrose.edu/sites/default/files/webform/talizovub.pdf In PDF document text
    • https://architecturaldesigninc.com/sites/default/files/sujuxot.pdfIn PDF document text
    • http://pilgrimland.com/sites/default/files/webform/resume-uploads/jitebetususi.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/nutuzisujobipusife.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/tojawi.pdfIn PDF document text
    • https://www.blplegal.com/sites/default/files/webform/piselusani.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/pidefukil.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/32675510575.pdfIn PDF document text
    • http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/nojezajewi.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/tinijozude.pdfIn PDF document text
    • https://extranet.blanchisserie-toulousaine-de-sante.com/sites/extranet.blanchisserie-toulousaine-de-sante.com/files/documents/justificatifs/pefusoxewirevujilo.pdfIn PDF document text
    • https://web.liderpapel.com/sites/default/files/webform/36759883892.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/bavowusakixonodokuja.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/zMnd8XtcwSM/uplcv?utm_term=what+is+conducting+material+in+physicsPDF link annotation
    • https://community.princeton.edu/system/files/webform/4167827641.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/pagilavamuvawasaxega.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e03c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE03C 5600 bytes
SHA-256: 90bef27ff594e7d1b515d1db6194bbe7f3ba5e951bca9ab3d982d235fbd5e6b8
font_01_sfnt_off0000f330.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF330 12232 bytes
SHA-256: 8b9faa0c1d6bdca1af594977736204ff74212aff8bb9fd2c986f0352726d2ac3
font_02_sfnt_off00011d05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D05 16100 bytes
SHA-256: c29374cd8bf96e71c4e8d7015a239404e06b34d72b71a19e3f6f198b87d8a8d0