CVE-2026-34303: 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. in Oracle Corporation MySQL Server
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.0-8.0.45, 8.4.0-8.4.8 and 9.0.0-9.6.0. 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).
AI Analysis
Technical Summary
This vulnerability exists in the Optimizer component of Oracle MySQL Server across multiple supported versions. It permits an attacker with low privileges and network access to cause a hang or repeated crashes, resulting in a complete denial of service. The CVSS 3.1 base score is 6.5, reflecting a medium severity with an impact on availability only. Oracle's April 2026 Critical Patch Update addresses this vulnerability among 481 other security fixes. The advisory strongly recommends applying the update without delay to prevent exploitation.
Potential Impact
Successful exploitation results in denial of service by causing the MySQL Server to hang or crash repeatedly. There is no impact on confidentiality or integrity. The vulnerability can be exploited remotely by a low privileged attacker with network access, potentially disrupting database availability.
Mitigation Recommendations
Oracle has released patches for this vulnerability in the April 2026 Critical Patch Update. Users should apply the relevant patches for MySQL Server versions 8.0.0-8.0.45, 8.4.0-8.4.8, and 9.0.0-9.6.0 as soon as possible. No alternative mitigations or workarounds are specified. Patch status is confirmed by the vendor advisory.
CVE-2026-34303: 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. in Oracle Corporation MySQL Server
Description
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.0-8.0.45, 8.4.0-8.4.8 and 9.0.0-9.6.0. 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).
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability exists in the Optimizer component of Oracle MySQL Server across multiple supported versions. It permits an attacker with low privileges and network access to cause a hang or repeated crashes, resulting in a complete denial of service. The CVSS 3.1 base score is 6.5, reflecting a medium severity with an impact on availability only. Oracle's April 2026 Critical Patch Update addresses this vulnerability among 481 other security fixes. The advisory strongly recommends applying the update without delay to prevent exploitation.
Potential Impact
Successful exploitation results in denial of service by causing the MySQL Server to hang or crash repeatedly. There is no impact on confidentiality or integrity. The vulnerability can be exploited remotely by a low privileged attacker with network access, potentially disrupting database availability.
Mitigation Recommendations
Oracle has released patches for this vulnerability in the April 2026 Critical Patch Update. Users should apply the relevant patches for MySQL Server versions 8.0.0-8.0.45, 8.4.0-8.4.8, and 9.0.0-9.6.0 as soon as possible. No alternative mitigations or workarounds are specified. Patch status is confirmed by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- oracle
- Date Reserved
- 2026-03-26T19:48:45.678Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.oracle.com/security-alerts/cpuapr2026.html","vendor":"Oracle"}]
Threat ID: 69e7e5a819fe3cd2cdf9f9a6
Added to database: 4/21/2026, 9:01:28 PM
Last enriched: 4/21/2026, 9:47:54 PM
Last updated: 4/22/2026, 6:40:44 AM
Views: 9
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