{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-77272", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-08-20T19:14:21.330Z", "datePublished": "2026-09-22T18:33:18.421Z", "dateUpdated": "2026-09-22T18:33:18.421Z"}, "containers": {"cna": {"title": "MCP Atlassian: Reflected XSS in OAuth Setup Callback Handler", "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": 5.4, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N", "version": "3.1"}}], "references": [{"name": "https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-g2r2-3j32-j27x", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-g2r2-3j32-j27x"}, {"name": "https://github.com/sooperset/mcp-atlassian/pull/1448", "tags": ["x_refsource_MISC"], "url": "https://github.com/sooperset/mcp-atlassian/pull/1448"}, {"name": "https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460", "tags": ["x_refsource_MISC"], "url": "https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460"}, {"name": "https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0", "tags": ["x_refsource_MISC"], "url": "https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0"}], "affected": [{"vendor": "sooperset", "product": "mcp-atlassian", "versions": [{"version": "< 0.22.0", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-09-22T18:33:18.421Z"}, "descriptions": [{"lang": "en", "value": "MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the OAuth error query parameter is passed to CallbackHandler._send_response in oauth_setup.py and interpolated into an HTML page without escaping. A crafted authorization callback can inject markup or script that executes in the browser of a user completing the OAuth flow. This issue is fixed in version 0.22.0."}], "source": {"advisory": "GHSA-g2r2-3j32-j27x", "discovery": "UNKNOWN"}}}}

{}

{"affected": [{"affectedData": [{"product": "mcp-atlassian", "vendor": "sooperset", "versions": [{"status": "affected", "version": "< 0.22.0"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "MCP Atlassian is a Model Context Protocol (MCP) server for Atlassian products (Confluence and Jira). Prior to 0.22.0, the OAuth error query parameter is passed to CallbackHandler._send_response in oauth_setup.py and interpolated into an HTML page without escaping. A crafted authorization callback can inject markup or script that executes in the browser of a user completing the OAuth flow. This issue is fixed in version 0.22.0."}], "id": "CVE-2026-77272", "lastModified": "2026-09-22T19:16:51.177", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.4, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 2.5, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-09-22T19:16:51.177", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/sooperset/mcp-atlassian/commit/b041733473f95119dd539542a43c280737a8e460"}, {"source": "security-advisories@github.com", "url": "https://github.com/sooperset/mcp-atlassian/pull/1448"}, {"source": "security-advisories@github.com", "url": "https://github.com/sooperset/mcp-atlassian/releases/tag/v0.22.0"}, {"source": "security-advisories@github.com", "url": "https://github.com/sooperset/mcp-atlassian/security/advisories/GHSA-g2r2-3j32-j27x"}], "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": "[0,0.22.0)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "mcp-atlassian", "source": "cna", "vendor": "sooperset"}, "product": "mcp-atlassian", "vendor": "sooperset"}], "created": "2026-09-22T19:30:14.701764+00:00", "updated": "2026-09-22T20:15:09.225901+00:00", "vendors": ["sooperset", "sooperset$PRODUCT$mcp-atlassian"]}