Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b772cb369415dcf…

MALICIOUS

PDF

70.3 KB Created: 2021-04-10 15:44:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 2064a41d83263d039a37e0572eeb7581 SHA-1: b67bc35e98d8501544ce0c50230ae0992ade886a SHA-256: 7b772cb369415dcf230ef84a6c85cb7add128b01344fe33e8b6b357a24b16d9f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

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.woonsocketri.org/system/temporary/webform/konoju.pdf In PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/59286961246.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/gurasijam.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/dekif.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/fabifuturofutip.pdfIn PDF document text
    • https://www.blplegal.com/sites/default/files/webform/89971565628.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/memirudomonejusowanasu.pdfIn PDF document text
    • http://spotlight-sites.com/sites/default/files/webform/sugugijokasu.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/rebunedirewe.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=canadian+citizenship+test+freePDF link annotation
    • https://www.healthdata.org/sites/default/files/resumes/muvebijamalixodimobowase.pdfIn PDF document text
    • https://minorsoncampus.princeton.edu/system/files/webform/27732669772.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/98562832035.pdfIn PDF document text
    • https://gradfutures.princeton.edu/system/files/webform/pelafo.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/22535495660.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c8f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8F0 4964 bytes
SHA-256: 3bdf0fac0479467657c9a54f866b06955434e3040b0c55502dac7795598e7d8b
font_01_sfnt_off0000d9d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9D0 10868 bytes
SHA-256: 0f89abaa3bad0505d63f0a3eb8a57a8639980c703bc826f431a25d31ae25a58e
font_02_sfnt_off0000fe53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE53 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3