{
  "containers": {
    "cna": {
      "affected": [
        {
          "product": "yamcs",
          "vendor": "yamcs",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 5.9.4"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Yamcs is a mission control framework. Prior to 5.9.4, Yamcs reflects an attacker-controlled redirect_uri parameter from GET /auth/authorize into yamcs-core/src/main/resources/auth/templates/authorize.html without adequate HTML escaping by yamcs-core/src/main/java/org/yamcs/http/auth/AuthHandler.java and yamcs-core/src/main/java/org/yamcs/http/HandlerContext.java. A crafted authorization URL can execute JavaScript when opened by a Yamcs user. The script can access browser-held authentication material and transmit it to an attacker, enabling account compromise. This issue is fixed in version 5.9.4."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 6.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-79",
              "description": "CWE-79: Improper Neutralization of Input During Web Page Generation (\u0027Cross-site Scripting\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-28T17:15:52.840Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/yamcs/yamcs/security/advisories/GHSA-rxpg-wjf8-qv9c",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/yamcs/yamcs/security/advisories/GHSA-rxpg-wjf8-qv9c"
        },
        {
          "name": "https://github.com/yamcs/yamcs/commit/4d47d5cdcf5d92c2c5bbbc19feada422923332e3",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/yamcs/yamcs/commit/4d47d5cdcf5d92c2c5bbbc19feada422923332e3"
        },
        {
          "name": "https://github.com/yamcs/yamcs/releases/tag/yamcs-5.9.4",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/yamcs/yamcs/releases/tag/yamcs-5.9.4"
        }
      ],
      "source": {
        "advisory": "GHSA-rxpg-wjf8-qv9c",
        "discovery": "UNKNOWN"
      },
      "title": "Yamcs: Reflected XSS in the URL of the Authorize Endpoint"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-55549",
    "datePublished": "2026-08-28T17:15:52.840Z",
    "dateReserved": "2026-06-16T23:01:04.075Z",
    "dateUpdated": "2026-08-28T17:15:52.840Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}