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{"bugzilla": {"description": "mysql: Optimizer unspecified vulnerability (CPU Jan 2026)", "id": "2431385", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2431385"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.9", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:H/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 8.0.0-8.0.44, 8.4.0-8.4.7 and 9.0.0-9.5.0. Easily exploitable vulnerability allows high 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 4.9 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H)."], "name": "CVE-2026-21948", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "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": "Affected", "package_name": "mysql:8.0/mysql", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "mysql:8.4/mysql", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "mysql", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "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-2026-21948\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-21948\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": "2026-04-18T15:40:30.740250+00:00", "value": {"mitigation_remediation": ["Apply the Oracle January 2026 security patch for MySQL Server, upgrading to a version newer than 8.0.44, 8.4.7, or 9.5.0 (e.g., 8.0.45, 8.4.8, or 9.6.0).", "Restrict network access to the MySQL service to trusted hosts or networks with firewall rules or security groups, limiting high\u2011privileged connections.", "Monitor MySQL logs for hang or crash events and configure automatic restart or high\u2011availability failover to reduce downtime."], "summary": {"action": "Apply Patch", "impact": "Denial of Service (Availability)"}, "threat_synthesis": {"affected_systems": "Oracle MySQL Server versions from 8.0.0 through 8.0.44, 8.4.0 through 8.4.7 and 9.0.0 through 9.5.0 are impacted. Users of these releases should confirm their environment version and plan an upgrade.", "description_and_impact": "The vulnerability resides in the Optimizer component of Oracle MySQL Server and allows a high privileged attacker who can reach the server over the network to cause the database to hang or crash repeatedly. This results in complete denial of service, affecting availability while confidentiality and integrity remain untouched. The weakness is a Resource Exhaustion flaw (CWE\u2011400).", "risk_and_exploitability": "With a CVSS 3.1 base score of 4.9 and an EPSS below 1%, the likelihood of exploitation is judged low, and the vulnerability is not listed in the CISA KEV catalog. The poisoning requires the attacker to have high privileges and network access; once achieved, the effect is a total service disruption. Existing mitigations such as limiting concurrent connections or disabling optimizations could reduce risk, but the most reliable protection comes from applying the official fix."}}}}, "created": "2026-04-18T15:45:04.274261+00:00", "updated": "2026-04-18T15:45:04.274272+00:00", "vendors": []}