{"document":{"category":"csaf_vex","csaf_version":"2.0","title":"CVE-2026-50631: Apache CXF: OAuth2: TOCTOU Race Condition in Refresh Token Processing","publisher":{"category":"vendor","name":"HarborGuard Database","namespace":"https://database.harborguard.co"},"tracking":{"id":"CVE-2026-50631","status":"final","version":"1","initial_release_date":"2026-06-12T08:59:40.200Z","current_release_date":"2026-06-12T14:04:22.866Z","revision_history":[{"date":"2026-06-12T08:59:40.200Z","number":"1","summary":"Initial machine-readable export from HarborGuard."}]},"distribution":{"tlp":{"label":"WHITE"},"text":"Public CVE data; freely redistributable."},"notes":[{"category":"description","text":"A race condition in AbstractOAuthDataProvider allows concurrent requests using the same Refresh Token to bypass single-use semantics and generate multiple valid Access Tokens, when 'recycleRefreshTokens' is set to false. A leaked refresh token can be replayed concurrently by multiple attackers or threads. Users are recommended to upgrade to versions 4.2.2 or 4.1.7, which fixes this issue.","title":"CVE description"}],"references":[{"category":"self","summary":"CVE-2026-50631 on HarborGuard Database","url":"https://database.harborguard.co/cve/CVE-2026-50631"},{"category":"external","summary":"CVE Record","url":"https://www.cve.org/CVERecord?id=CVE-2026-50631"},{"category":"external","summary":"lists.apache.org","url":"https://lists.apache.org/thread/s83t3x4r626o9h8rt0ryr1w7w53l1vv8"}]},"product_tree":{"branches":[{"category":"vendor","name":"Apache Software Foundation","branches":[{"category":"product_name","name":"Apache CXF","branches":[{"category":"product_version_range","name":">=4.2.0 <4.2.2","product":{"name":"Apache Software Foundation Apache CXF >=4.2.0 <4.2.2","product_id":"CSAFPID-1","product_identification_helper":{"cpe":"cpe:2.3:a:apache_software_foundation:apache_cxf:*:*:*:*:*:*:*:*"}}},{"category":"product_version_range","name":"<4.1.7","product":{"name":"Apache Software Foundation Apache CXF <4.1.7","product_id":"CSAFPID-2","product_identification_helper":{"cpe":"cpe:2.3:a:apache_software_foundation:apache_cxf:*:*:*:*:*:*:*:*"}}}]}]}]},"vulnerabilities":[{"cve":"CVE-2026-50631","title":"Apache CXF: OAuth2: TOCTOU Race Condition in Refresh Token Processing","notes":[{"category":"description","text":"A race condition in AbstractOAuthDataProvider allows concurrent requests using the same Refresh Token to bypass single-use semantics and generate multiple valid Access Tokens, when 'recycleRefreshTokens' is set to false. A leaked refresh token can be replayed concurrently by multiple attackers or threads. Users are recommended to upgrade to versions 4.2.2 or 4.1.7, which fixes this issue.","title":"CVE description"}],"product_status":{"known_affected":["CSAFPID-1","CSAFPID-2"]},"scores":[{"cvss_v3":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N","baseScore":7.4,"baseSeverity":"HIGH"},"products":["CSAFPID-1","CSAFPID-2"]}],"remediations":[{"category":"vendor_fix","details":"Update to a fixed version: 4.1.7, 4.2.2.","product_ids":["CSAFPID-1","CSAFPID-2"]}]}]}