Malicious PDF — malware analysis report

Static analysis result for SHA-256 24523db6f3f11264…

MALICIOUS

PDF

30.9 KB Created: 2018-06-11 08:56:39 -04:00 Authoring application: wkhtmltopdf 0.12.4 (via Qt 4.8.7) First seen: 2020-09-24
MD5: 9f87d100fa81419a20ee09378987ba4a SHA-1: c5ec6497a90c69382bb821516b8f11029d059694 SHA-256: 24523db6f3f11264262932d010e368354e21add76699d7c758a5c68d3351b830
130 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment

The PDF contains embedded URLs and a heuristic firing for PDF_URI points to a suspicious domain, uncpbisdegree.com, which is likely used for delivering a malicious payload. The document body also contains a visual download lure, reinforcing the deceptive nature of the file. The ML classifier also flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9545

Heuristics 4

  • Fake 'free download' SEO-poisoning PDF critical PDF_SEO_FAKE_DOWNLOAD
    The ML classifier flagged this PDF AND it carries a visual download/call-to-action lure AND an off-domain server-side download-gateway link whose query string names a document payload. This three-signal conjunction is the fake-document / 'free PDF download' SEO-poisoning delivery pattern: the page is padded with benign decoy links to dilute classifier scores while funnelling the victim through the gateway to malware/scareware. Acting only on the conjunction keeps benign download-bearing PDFs from being misflagged.
  • PDF carries a PHP-gateway SEO-spam PDF link farm medium PDF_SEO_PHP_GATEWAY_LINK_FARM
    PDF contains four or more clickable links whose target is a `.php` gateway with a multi-word search-PHRASE document slug embedded after it (e.g. 'index.php?.../binary+options+trading+nz.pdf' or 'pdf.php/cialis-dosage-side-effects.pdf'). Legitimate PHP-served documents use a filename or numeric id, not a search-query phrase, so this is the generated SEO link-farm shape — pharma / binary-options / 'free download' spam that ranks for queries and routes users into payload/redirect chains. The PDF itself carries no exploit — the risk is the linked destinations.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 http://uncpbisdegree.com/download3.php?q=transport-processes-and-separation-process-principles-includes-unit-ope.pdf In PDF document text
    • http://uncpbisdegree.com/download4.php?q=transport-processes-and-separation-process-principles-includes-unit-ope.pdfIn PDF document text
    • http://www.dacworldwide.com/searchIn PDF document text
    • https://worksafe.govt.nz/the-toolshed/definitions-and-acronyms/In PDF document text
    • http://www.ukexportnews.co.uk/search.phpIn PDF document text
    • http://www.new-territories.com/blog/In PDF document text
    • http://www.hnn.bz/In PDF document text
    • http://www.thecleanzine.com/search.php?q=andIn PDF document text
    • https://www.ihes.fr/bibliotheque/In PDF document text
    • http://riverside-resort.net/1/spaccato-motore-lombardini-lda-510.pdfIn PDF document text
    • http://riverside-resort.net/1/spectra-series-power-panelboards-ge-industrial.pdfIn PDF document text
    • http://riverside-resort.net/1/sfa-stenosis.pdfIn PDF document text
    • http://riverside-resort.net/1/the-portable-jack-kerouac.pdfIn PDF document text
    • http://riverside-resort.net/1/the-matsushita-perspective-a-business-philosophy-handbook.pdfIn PDF document text
    • http://riverside-resort.net/1/taylor-forklift-manual.pdfIn PDF document text
    • http://riverside-resort.net/1/seti-el-nino-egipcio.pdfIn PDF document text
    • http://riverside-resort.net/1/seiko-snd401-watches-owners-manual.pdfIn PDF document text
    • http://riverside-resort.net/1/toyota-hiace-manual-diesel.pdfIn PDF document text
    • http://riverside-resort.net/1/take-back-your-life-recovering-from-cults-and-abusive-relationships.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://www.federalregister.gov/documents/2015/04/17/2015-00257/hazardous-and-solid-waste-management-system-disposal-of-coal-combustion-residuals-from-electricIn PDF document text
    • https://news.un.org/en/In PDF document text
    • https://www.sciencedirect.com/science/article/pii/S0079642517300968In PDF document text
    • http://www.loot.co.za/index/html/index3385.htmlIn PDF document text
    • http://slatestarcodex.com/2018/02/27/links-2-18-link-biao-incident/In PDF document text
    • http://www.microsofttranslator.com/bv.aspx?ref=SERP&br=ro&mkt=en-US&dl=en&lp=FR_EN&a=https%3a%2f%2fwww.ihes.fr%2fbibliotheque%2fIn PDF document text
    • http://go.microsoft.com/fwlink/?LinkId=521839&CLCID=0409In PDF document text
    • http://go.microsoft.com/fwlink/?LinkID=246338&CLCID=0409In PDF document text
    • https://go.microsoft.com/fwlink/?linkid=868922In PDF document text
    • http://go.microsoft.com/fwlink/?LinkID=286759&CLCID=409In PDF document text
    • http://go.microsoft.com/fwlink/?LinkID=617297In PDF document text
    • https://fedoraproject.org/wiki/Licensing/LiberationFontLicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00004017.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x4017 10064 bytes
SHA-256: 0a8fda3943a2a277045579460c55524496acbbbcb363d589fe0a69ed0f266f94
font_01_sfnt_off00006016.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6016 6768 bytes
SHA-256: 8032662916598db70bb46fae2dbc4f7dd51400c4fc537a8082fe0284db2d2d5e