Malicious PDF — malware analysis report

Static analysis result for SHA-256 fe815b8c0c09ace8…

MALICIOUS

PDF

78.6 KB Created: 2021-04-22 11:16:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 36cec37a8a75289915253dd924f5a688 SHA-1: 0edfb5dbc975dfb0142a1fbf53c8a2dda93919e7 SHA-256: fe815b8c0c09ace8e4f49960861d9af5a553d6080faab1f87c03835e2eb0f12f
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://aboss.by/sites/default/files/webform/80384466065.pdf In PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/jedirokadezat.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/22559513310.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/vopezupudatirarib.pdfIn PDF document text
    • https://www.jwico.com/sites/default/files/webform/69174909787.pdfIn PDF document text
    • https://www.jsif.org/sites/default/files/webform/vinuriruxelapaviwona.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/vonasajevevedatenalezeb.pdfIn PDF document text
    • https://www.telluridescience.org/sites/default/files/tstc-applications/30232074114.pdfIn PDF document text
    • https://vectorcorp.net/sites/default/files/webform/resume/wogudodijanaferewinige.pdfIn PDF document text
    • https://www.mainephilanthropy.org/sites/default/files/guvobirewuge.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/BvfzZFkJO3s/uplcv?utm_term=how+to+fix+brain+fog+quicklyPDF link annotation
    • https://printandmail.princeton.edu/system/files/webform/50156150340.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/13590028771.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/piwolumubixu.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/febapaxugodikuzakepob.pdfIn PDF document text
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/1901815882.pdfIn PDF document text
    • https://gradfutures.princeton.edu/system/files/webform/xafuzekimizitigemuseli.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_off0000f40f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF40F 5424 bytes
SHA-256: 5430c64662d677a2293c977ae5cd0552f4a1d514c713af8d502fbd2f0da96e2f
font_01_sfnt_off000106b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106B1 11080 bytes
SHA-256: 34c90165ff8b5d77e506219f61be443e74c915b6bad520191def880a5ea3caa9