Malicious PDF — malware analysis report

Static analysis result for SHA-256 82459dfc6f80c3af…

MALICIOUS

PDF

35.1 KB Created: 2018-06-11 08:17:15 -04:00 Authoring application: wkhtmltopdf 0.12.4 (via Qt 4.8.7) First seen: 2020-09-24
MD5: a7516304d97c59c9119b2773cd092c28 SHA-1: 874fcaf1a3cef9a478ec7aeea8f14752286be8c8 SHA-256: 82459dfc6f80c3af014ec863320691bb7a4d9847122cce2070d821fb5a758b94
102 Risk Score

Malware Insights

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

The PDF is flagged by multiple heuristics as a fake download lure using SEO poisoning. The document body and extracted URLs point to a domain designed to trick users into downloading a file, likely a malicious payload, by disguising it as an answer key. The ML classifier also strongly indicates maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9395

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.
  • 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
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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=water-and-its-properties-answer-key.pdf PDF link annotation
    • http://uncpbisdegree.com/download4.php?q=water-and-its-properties-answer-key.pdfIn PDF document text
    • http://www.lab35.net/assignments/bookIn PDF document text
    • http://www.chem4kids.com/files/matter_states.htmlIn PDF document text
    • https://neostencil.com/kpsc-kas-prelims-answer-key-kpsc-cut-off/In PDF document text
    • http://www.chem4kids.com/files/matter_mixture.htmlIn PDF document text
    • http://www.foamular.com/assets/0/144/172/174/e45fe07d-5cc9-4e4b-866a-5e35d75090ec.pdfIn PDF document text
    • http://www.middleschoolchemistry.com/lessonplans/chapter3/lesson3In PDF document text
    • https://chemfiesta.org/In PDF document text
    • http://www.glencoe.com/sites/common_assets/science/virtual_labs/E22/E22.htmlIn PDF document text
    • http://www.skintightening-cream.com/In PDF document text
    • http://www.laleva.cc/environment/water.htmlIn PDF document text
    • http://gavirtuallearning.org/In PDF document text
    • http://www.chem1.com/CQ/wonkywater.htmlIn PDF document text
    • http://www.crickweb.co.uk/ks2science.htmlIn PDF document text
    • http://uncpbisdegree.com/1/sift-features-matlab-code.pdfIn PDF document text
    • http://riverside-resort.net/1/writing-and-balancing-chemical-reactions.pdfIn PDF document text
    • http://uncpbisdegree.com/1/tarot-herm-tico-cabal-stico-alqu-mico.pdfIn PDF document text
    • http://riverside-resort.net/1/visiting-card-new-design-free-download.pdfIn PDF document text
    • http://uncpbisdegree.com/1/service-manual-for-case-skid-steer-85xt.pdfIn PDF document text
    • http://uncpbisdegree.com/1/tesccc-unit-8-lesson-4-world-history.pdfIn PDF document text
    • http://uncpbisdegree.com/1/texas-telecommmunicator-study-guide.pdfIn PDF document text
    • http://uncpbisdegree.com/1/spectralink-tgh116-routers-owners-manual.pdfIn PDF document text
    • http://uncpbisdegree.com/1/synthetic-oil-on-6-cyl-tundra-engines.pdfIn PDF document text
    • http://riverside-resort.net/1/where-are-goulds-pumps-made.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://en.wikipedia.org/wiki/Properties_of_waterIn PDF document text
    • https://en.wikipedia.org/wiki/Heavy_waterIn PDF document text
    • http://www.explainthatstuff.com/water.htmlIn PDF document text
    • http://www.explainthatstuff.com/articles_materials.htmlIn PDF document text
    • https://www.khanacademy.org/science/biology/water-acids-and-bases/hydrogen-bonding-in-water/a/water-as-a-solventIn PDF document text
    • https://www.khanacademy.org/science/biologyIn PDF document text
    • https://www.khanacademy.org/science/biology/water-acids-and-basesIn PDF document text
    • http://www.insightsonindia.com/2016/08/09/answer-key-upsc-prelims-2016/In PDF document text
    • http://www.insightsonindia.com/2015/08/27/answer-key-upsc-civil-services-preliminary-exam-2015-general-studies-paper-1/In PDF document text
    • https://www.ulta.com/photo-finish-primer-water?productId=xlsImpprod11741049In PDF document text
    • https://www.ulta.com/makeup?N=26y1In PDF document text
    • https://www.ulta.com/makeup-face?N=26y3In PDF document text
    • https://www.ulta.com/makeup-face-primer?N=26y4In PDF document text
    • https://opentextbc.ca/geology/back-matter/appendix-2-answers-to-review-questions/In PDF document text
    • http://www.dailymail.co.uk/sciencetech/article-3741337/Is-answer-clean-drinking-water-New-filter-rapidly-kill-bacteria-using-light-SUN.htmlIn PDF document text
    • http://nineplanets.org/data1.htmlIn PDF document text
    • https://bible.org/article/scriptural-use-archetype-waterIn 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_off00004d4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x4D4A 10552 bytes
SHA-256: 573a240d22db239f4f95ce4e4a3623bf0f5f3bde2d0b0c8f6332cdde58ac5cf5
font_01_sfnt_off00006eb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6EB0 6820 bytes
SHA-256: f56ac2138d7a0101a605152977371d5545a5fac07781f5a3ee2d644daac7af35