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    4 vulnerabilities found for showdown by showdown

    CVE-2026-59710 (GCVE-0-2026-59710)

    Vulnerability from nvd – Published: 2026-07-06 21:15 – Updated: 2026-07-07 13:47
    VLAI
    Title
    showdown - Stored XSS via Unescaped Table Header ID Attribute Injection
    Summary
    showdown contains a stored cross-site scripting vulnerability in the parseHeaders function of src/subParsers/makehtml/tables.js that fails to properly escape table header ID attributes. Attackers can inject arbitrary HTML and script-executing SVG elements through double-quote characters in markdown table headers, achieving stored XSS when untrusted markdown is rendered with the default github flavor configuration.
    SSVC
    Exploitation: poc Automatable: no Technical Impact: partial
    CISA Coordinator (v2.0.3)
    CWE
    • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
    Assigner
    Impacted products
    Vendor Product Version
    showdown showdown Affected: 0 , ≤ 2.1.0 (semver)
    Create a notification for this product.
    Date Public
    2026-03-12 00:00
    Credits
    Scott Moore - VulnCheck
    Show details on NVD website

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    CVE-2026-59711 (GCVE-0-2026-59711)

    Vulnerability from nvd – Published: 2026-07-06 21:00 – Updated: 2026-07-07 14:06
    VLAI
    Title
    showdown - Cross-Site Scripting via Unescaped Metadata Title in completeHTMLDocument
    Summary
    showdown contains a cross-site scripting vulnerability in metadata title handling that allows attackers to inject arbitrary HTML and JavaScript. When completeHTMLDocument option is enabled, unescaped less-than and greater-than characters in markdown frontmatter metadata are inserted directly into HTML title tags, enabling attackers to break out of the title context and execute malicious scripts in the rendered page.
    SSVC
    Exploitation: poc Automatable: no Technical Impact: partial
    CISA Coordinator (v2.0.3)
    CWE
    • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
    Assigner
    Impacted products
    Vendor Product Version
    showdown showdown Affected: 0 , ≤ 2.1.0 (semver)
    Create a notification for this product.
    Date Public
    2026-03-12 00:00
    Credits
    Scott Moore - VulnCheck
    Show details on NVD website

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    CVE-2026-59710 (GCVE-0-2026-59710)

    Vulnerability from cvelistv5 – Published: 2026-07-06 21:15 – Updated: 2026-07-07 13:47
    VLAI
    Title
    showdown - Stored XSS via Unescaped Table Header ID Attribute Injection
    Summary
    showdown contains a stored cross-site scripting vulnerability in the parseHeaders function of src/subParsers/makehtml/tables.js that fails to properly escape table header ID attributes. Attackers can inject arbitrary HTML and script-executing SVG elements through double-quote characters in markdown table headers, achieving stored XSS when untrusted markdown is rendered with the default github flavor configuration.
    SSVC
    Exploitation: poc Automatable: no Technical Impact: partial
    CISA Coordinator (v2.0.3)
    CWE
    • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
    Assigner
    Impacted products
    Vendor Product Version
    showdown showdown Affected: 0 , ≤ 2.1.0 (semver)
    Create a notification for this product.
    Date Public
    2026-03-12 00:00
    Credits
    Scott Moore - VulnCheck
    Show details on NVD website

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    CVE-2026-59711 (GCVE-0-2026-59711)

    Vulnerability from cvelistv5 – Published: 2026-07-06 21:00 – Updated: 2026-07-07 14:06
    VLAI
    Title
    showdown - Cross-Site Scripting via Unescaped Metadata Title in completeHTMLDocument
    Summary
    showdown contains a cross-site scripting vulnerability in metadata title handling that allows attackers to inject arbitrary HTML and JavaScript. When completeHTMLDocument option is enabled, unescaped less-than and greater-than characters in markdown frontmatter metadata are inserted directly into HTML title tags, enabling attackers to break out of the title context and execute malicious scripts in the rendered page.
    SSVC
    Exploitation: poc Automatable: no Technical Impact: partial
    CISA Coordinator (v2.0.3)
    CWE
    • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
    Assigner
    Impacted products
    Vendor Product Version
    showdown showdown Affected: 0 , ≤ 2.1.0 (semver)
    Create a notification for this product.
    Date Public
    2026-03-12 00:00
    Credits
    Scott Moore - VulnCheck
    Show details on NVD website

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