Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef2cbe7c48e44529…

MALICIOUS

PDF

74.5 KB Created: 2021-04-19 12:08:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: d72aa0583bb971e57e633bb60892089c SHA-1: a86283d3827539804a2d562f2f5111f860d6b388 SHA-256: ef2cbe7c48e44529e70cda2d8805c8891d915b96c00f31fe9c18f394aa7912ad
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://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/xetomaroronep.pdf In PDF document text
    • https://vectorcorp.net/sites/default/files/webform/resume/danodajanenalidadalibebav.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/bekam.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/22435641867.pdfIn PDF document text
    • https://www.visitsavannah.com/sites/default/files/webform/fukixuliwidopisoduzurapi.pdfIn PDF document text
    • https://www.a1touchsolution.nl/sites/default/files/95216779236.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/72917344941.pdfIn PDF document text
    • https://www.pharoxglobal.com/sites/default/files/webform/27804174203.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/jedirokadezat.pdfIn PDF document text
    • https://www.jsif.org/sites/default/files/webform/rijuluzevowogadabiwi.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/kepasibadugemefobovabo.pdfIn PDF document text
    • https://architecturaldesigninc.com/sites/default/files/vudezuluxi.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/PmAiG5ZyT-k/uplcv?utm_term=rod+of+7+parts+5ePDF link annotation
    • https://gradfutures.princeton.edu/system/files/webform/42179508969.pdfIn PDF document text
    • https://ubmemeaensoprod.s3.amazonaws.com/ifsec_international/call_for_papers/2021/03/kizoromafogikigogusebef.pdfIn PDF document text
    • https://www.healthdata.org/sites/default/files/resumes/jojilekavoxojomoz.pdfIn PDF document text
    • https://gradfutures.princeton.edu/system/files/webform/86626084736.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/50075528518.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_off0000e425.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE425 5216 bytes
SHA-256: 318a1ab217de6b2accb9a7c879251e471316cf7c7be927a2fb8075d14f5d5a62
font_01_sfnt_off0000f602.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF602 11380 bytes
SHA-256: 557086cb407188323b18d1d8b4be63450c7c6cd191e27f6c240519449fed4dae