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    2 vulnerabilities by showdownjs

    CVE-2026-104477 (GCVE-0-2026-104477)

    Vulnerability from cvelistv5 – Published: 2026-10-02 23:28 – Updated: 2026-10-02 23:28
    VLAI
    Title
    Showdown through 2.1.0 XSS via unescaped quote in href and src attributes
    Summary
    Showdown through 2.1.0 contains a cross-site scripting vulnerability in the makehtml link and image subparsers, which fail to escape double quotes in destination URLs placed into href and src attributes. Attackers can craft markdown links or images containing a double quote followed by onerror or onmouseover handlers to execute script when victims view rendered HTML.
    Severity
    5.3 (Medium)
    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N
    6.1 (Medium)
    CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
    CWE
    • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
    Assigner
    References
    Impacted products
    Vendor Product Version
    showdownjs showdown Affected: 0 , ≤ 2.1.0 (semver)
        cpe:2.3:a:showdownjs:showdown:*:*:*:*:*:*:*:*
    		Create a notification for this product.
    Date Public
    2026-06-27 00:00
    Credits
    Muhammad Sobirov
    Show details on NVD website
    To clipboard 

    {
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          "url": "https://github.com/showdownjs/showdown"
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      ],
      "title": "Showdown through 2.1.0 XSS via unescaped quote in href and src attributes",
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  "cveMetadata": {
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    "datePublished": "2026-10-02T23:28:47.414Z",
    "dateReserved": "2026-10-02T00:55:58.388Z",
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    CVE-2024-1899 (GCVE-0-2024-1899)

    Vulnerability from cvelistv5 – Published: 2024-02-26 18:45 – Updated: 2024-08-01 18:56
    VLAI
    Title
    Showdownjs Denial of Service
    Summary
    An issue in the anchors subparser of Showdownjs versions <= 2.1.0 could allow a remote attacker to cause denial of service conditions.
    Severity
    5.3 (Medium)
    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
    SSVC
    Exploitation: poc Automatable: yes Technical Impact: partial
    CISA Coordinator · CISA-ADP (v2.0.3)
    Decision recorded 2024-02-27 15:00 UTC
    CWE
    Assigner
    References
    Impacted products
    Vendor Product Version
    Showdownjs Showdown Affected: 0 , ≤ 2.1.0 (custom)
    		Create a notification for this product.
    showdownjs showdown Affected: 0 , ≤ 2.1.0 (custom)
        cpe:2.3:a:showdownjs:showdown:*:*:*:*:*:*:*:*
    		Create a notification for this product.
    Show details on NVD website
    To clipboard 

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            "product": "showdown",
            "vendor": "showdownjs",
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                "status": "affected",
                "version": "0",
                "versionType": "custom"
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        "metrics": [
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                  },
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                  },
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                  }
                ],
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                "timestamp": "2024-02-27T15:00:09.096812Z",
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          }
        ],
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      },
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        "providerMetadata": {
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              "value": "\u003cspan style=\"background-color: rgb(255, 255, 255);\"\u003eAn issue in the anchors subparser of Showdownjs versions \u0026lt;= 2.1.0 could allow a remote attacker to cause denial of service conditions.\u003c/span\u003e\u003cbr\u003e"
            }
          ],
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      "metrics": [
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            "attackVector": "NETWORK",
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