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{"bugzilla": {"description": "mysql: Optimizer unspecified vulnerability (CPU Jan 2026)", "id": "2431434", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2431434"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.5", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "details": ["Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 9.0.0-9.5.0. Easily exploitable vulnerability allows low privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server. CVSS 3.1 Base Score 6.5 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)."], "name": "CVE-2026-21949", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "mysql8.4", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "mysql", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "mysql:8.0/mysql", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "mysql:8.4/mysql", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "mysql", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "mysql:8.4/mysql", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-01-20T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-21949\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-21949\nhttps://www.oracle.com/security-alerts/cpujan2026.html#AppendixMSQL"], "statement": "Red Hat Product Security rates the severity of this flaw as determined by the Oracle MySQL Critical Patch Update.", "threat_severity": "Moderate"}

{"analysis": {"en": {"generated_at": "2026-04-18T04:32:12.932592+00:00", "value": {"mitigation_remediation": ["Apply the Oracle MySQL Server patch released for the January\u202f2026 CPU, which addresses the optimizer bug and restores stability.", "After updating, restart the MySQL service and verify that the server accepts connections and processes queries normally.", "If patching cannot be performed immediately, isolate the database server from untrusted networks and tightly control firewall rules to limit exposure to the known vulnerable protocols.", "Monitor MySQL logs for unexpected hangs or terminate signals and apply additional rate\u2011limiting on query submission to mitigate accidental resource exhaustion."], "summary": {"action": "Apply patch", "impact": "Denial of Service"}, "threat_synthesis": {"affected_systems": "Oracle MySQL Server versions from 9.0.0 through 9.5.0 are affected. Administrators should verify the exact build and apply the security patch provided by Oracle for these releases.", "description_and_impact": "The vulnerability resides in the Optimizer component of Oracle MySQL Server and is classified as a resource consumption flaw (CWE\u2011400). Exploitation can cause the server to hang or repeatedly crash, resulting in a complete denial of service to any application or user relying on the database.", "risk_and_exploitability": "With a CVSS base score of 6.5, the vulnerability primarily impacts availability. The EPSS score is below 1\u202f%, indicating a low probability of exploitation, and it is currently not listed in the CISA KEV catalogue. The likely attack vector is a remote, low\u2011privileged network user sending specially crafted SQL statements over supported protocols, which triggers the optimizer bug and causes the service to crash."}}}}, "created": "2026-04-18T04:45:36.861733+00:00", "updated": "2026-04-18T04:45:36.861752+00:00", "vendors": []}