{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-55549", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-06-16T23:01:04.075Z", "datePublished": "2026-08-28T17:15:52.840Z", "dateUpdated": "2026-08-28T17:15:52.840Z"}, "containers": {"cna": {"title": "Yamcs: Reflected XSS in the URL of the Authorize Endpoint", "problemTypes": [{"descriptions": [{"cweId": "CWE-79", "lang": "en", "description": "CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')", "type": "CWE"}]}], "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"}}], "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"}], "affected": [{"vendor": "yamcs", "product": "yamcs", "versions": [{"version": "< 5.9.4", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-08-28T17:15:52.840Z"}, "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."}], "source": {"advisory": "GHSA-rxpg-wjf8-qv9c", "discovery": "UNKNOWN"}}}}

{}

{"affected": [{"affectedData": [{"product": "yamcs", "vendor": "yamcs", "versions": [{"status": "affected", "version": "< 5.9.4"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "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."}], "id": "CVE-2026-55549", "lastModified": "2026-08-28T20:18:28.657", "metrics": {"cvssMetricV31": [{"cvssData": {"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"}, "exploitabilityScore": 2.8, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-08-28T20:18:28.657", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/yamcs/yamcs/commit/4d47d5cdcf5d92c2c5bbbc19feada422923332e3"}, {"source": "security-advisories@github.com", "url": "https://github.com/yamcs/yamcs/releases/tag/yamcs-5.9.4"}, {"source": "security-advisories@github.com", "url": "https://github.com/yamcs/yamcs/security/advisories/GHSA-rxpg-wjf8-qv9c"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Received", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-79"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,5.9.4)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "yamcs", "source": "cna", "vendor": "yamcs"}, "product": "yamcs", "vendor": "yamcs"}], "created": "2026-08-28T21:30:05.386710+00:00", "updated": "2026-08-28T21:45:03.386164+00:00", "vendors": ["yamcs", "yamcs$PRODUCT$yamcs"]}