{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-34278", "assignerOrgId": "43595867-4340-4103-b7a2-9a5208d29a85", "state": "PUBLISHED", "assignerShortName": "oracle", "dateReserved": "2026-03-26T19:48:45.675Z", "datePublished": "2026-04-21T20:35:19.579Z", "dateUpdated": "2026-04-21T20:35:19.579Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "43595867-4340-4103-b7a2-9a5208d29a85", "shortName": "oracle", "dateUpdated": "2026-04-21T20:35:19.579Z"}, "problemTypes": [{"descriptions": [{"lang": "en-US", "description": "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."}]}], "affected": [{"vendor": "Oracle Corporation", "product": "MySQL Server", "versions": [{"version": "8.0.0", "status": "affected", "lessThanOrEqual": "8.0.45", "versionType": "custom"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:oracle:mysql_server:*:*:*:*:*:*:*:*", "versionStartIncluding": "8.0.0", "versionEndIncluding": "8.0.45"}]}]}], "descriptions": [{"lang": "en-US", "value": "Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.0-8.0.45. 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)."}], "references": [{"url": "https://www.oracle.com/security-alerts/cpuapr2026.html", "name": "Oracle Advisory", "tags": ["vendor-advisory"]}], "metrics": [{"cvssV3_1": {"attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "HIGH", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH", "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H", "baseScore": 4.9, "baseSeverity": "MEDIUM"}}]}}}

{}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.0-8.0.45. 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)."}], "id": "CVE-2026-34278", "lastModified": "2026-04-21T21:16:32.027", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 4.9, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "HIGH", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.2, "impactScore": 3.6, "source": "secalert_us@oracle.com", "type": "Primary"}]}, "published": "2026-04-21T21:16:32.027", "references": [{"source": "secalert_us@oracle.com", "url": "https://www.oracle.com/security-alerts/cpuapr2026.html"}], "sourceIdentifier": "secalert_us@oracle.com", "vulnStatus": "Received"}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[8.0.0,8.0.45]"}}], "enrichment": {"confidence": 95.0, "confidence_source": "inferred", "scores": [{"score": 95.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "MySQL Server", "source": "cna", "vendor": "Oracle Corporation"}, "product": "mysql_server", "vendor": "oracle"}], "analysis": {"en": {"generated_at": "2026-04-22T05:06:10.275272+00:00", "value": {"mitigation_remediation": ["Apply the latest Oracle MySQL Server update that addresses the optimizer crash.", "Restrict network exposure of the MySQL server, allowing connections only from trusted hosts and eliminating unnecessary protocol access.", "Configure the operating system or application monitoring to detect unexpected restarts and automatically restart the database service to mitigate downtime."], "summary": {"action": "Update", "impact": "Denial of Service (high privileged attacker can cause crash)"}, "threat_synthesis": {"affected_systems": "Oracle MySQL Server, versions 8.0.0 through 8.0.45, are affected. Any deployment of these versions that allows optimizer execution over the network is at risk.", "description_and_impact": "The vulnerability resides in the Optimizer component of Oracle MySQL Server, allowing a high privileged attacker with network access to trigger a crash of the server. The exploit is described as easily exploitable, and the resulting crash can be repeatedly induced, thereby causing a denial of service to all clients. The attack requires high privileges but remains accessible over the network, and the impact affects availability rather than confidentiality or integrity.", "risk_and_exploitability": "The CVSS v3.1 base score is 4.9, reflecting a moderate severity but with a high availability impact. EPSS is not available and the vulnerability is not listed in the CISA KEV catalog. Nonetheless, the description indicates that the flaw is easily exploitable by a high privileged attacker who can access the server via supported protocols, enabling them to repeatedly crash the database service. While the attack requires elevated privileges, the potential availability disruption warrants prompt remediation."}}}}, "created": "2026-04-22T02:30:05.481379+00:00", "title": "High-Privilege Network-Exploitable Denial of Service in MySQL Server Optimizer", "updated": "2026-04-22T05:15:06.067753+00:00", "vendors": ["oracle", "oracle$PRODUCT$mysql_server"], "weaknesses": ["CWE-754"]}