Vulnerability · Published Apr 21, 2026 · Assigned by oracle

CVE-2026-34303

Medium 6.5

In plain English

A medium-severity uncontrolled resource consumption in MySQL Server from Oracle Corporation. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 23% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)6.5Medium
Exploit odds (30 days)0.3%top 76.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official 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).

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
AlmaLinux:8mecab0.996-2.module_el8.6.0+3340+d764b636ALSA-2026:25919
AlmaLinux:8mecab0.996-2.module_el8.10.0+4060+d4256e26ALSA-2026:26180
AlmaLinux:8mecab0.996-2.module_el8.10.0+3965+b415b607ALSA-2026:25919
AlmaLinux:9mecab0.996-3.module_el9.6.0+152+8cbce00c.4ALSA-2026:25052
AlmaLinux:8mecab-devel0.996-2.module_el8.10.0+4060+d4256e26ALSA-2026:26180
AlmaLinux:8mecab-devel0.996-2.module_el8.10.0+3965+b415b607ALSA-2026:25919
AlmaLinux:8mecab-devel0.996-2.module_el8.6.0+3340+d764b636ALSA-2026:25919
AlmaLinux:9mecab-devel0.996-3.module_el9.6.0+152+8cbce00c.4ALSA-2026:25052
AlmaLinux:8mecab-ipadic2.7.0.20070801-17.module_el8.10.0+4060+d4256e26ALSA-2026:26180
AlmaLinux:8mecab-ipadic2.7.0.20070801-17.module_el8.10.0+4154+a69a9128ALSA-2026:26180
AlmaLinux:8mecab-ipadic2.7.0.20070801-17.module_el8.10.0+4142+0b28b031ALSA-2026:25919
AlmaLinux:8mecab-ipadic2.7.0.20070801-17.module_el8.10.0+3965+b415b607ALSA-2026:25919
AlmaLinux:9mecab-ipadic2.7.0.20070801-24.module_el9.6.0+152+8cbce00cALSA-2026:25052
AlmaLinux:8mecab-ipadic-EUCJP2.7.0.20070801-17.module_el8.10.0+4060+d4256e26ALSA-2026:26180
AlmaLinux:8mecab-ipadic-EUCJP2.7.0.20070801-17.module_el8.10.0+3965+b415b607ALSA-2026:25919
AlmaLinux:8mecab-ipadic-EUCJP2.7.0.20070801-17.module_el8.10.0+4142+0b28b031ALSA-2026:25919
AlmaLinux:8mecab-ipadic-EUCJP2.7.0.20070801-17.module_el8.10.0+4154+a69a9128ALSA-2026:26180
AlmaLinux:9mecab-ipadic-EUCJP2.7.0.20070801-24.module_el9.6.0+152+8cbce00cALSA-2026:25052
AlmaLinux:8mysql8.4.9-1.module_el8.10.0+4193+cbb8e728ALSA-2026:26180
AlmaLinux:8mysql8.0.46-1.module_el8.10.0+4192+724bc664ALSA-2026:25919
AlmaLinux:9mysql8.0.46-1.el9_8ALSA-2026:23332
AlmaLinux:9mysql8.4.9-1.module_el9.8.0+263+ff5e95cfALSA-2026:25052
AlmaLinux:8mysql-common8.4.9-1.module_el8.10.0+4193+cbb8e728ALSA-2026:26180
AlmaLinux:8mysql-common8.0.46-1.module_el8.10.0+4192+724bc664ALSA-2026:25919
AlmaLinux:9mysql-common8.4.9-1.module_el9.8.0+263+ff5e95cfALSA-2026:25052
AlmaLinux:9mysql-common8.0.46-1.el9_8ALSA-2026:23332
AlmaLinux:8mysql-devel8.4.9-1.module_el8.10.0+4193+cbb8e728ALSA-2026:26180
AlmaLinux:8mysql-devel8.0.46-1.module_el8.10.0+4192+724bc664ALSA-2026:25919
AlmaLinux:9mysql-devel8.0.46-1.el9_8ALSA-2026:23332
AlmaLinux:9mysql-devel8.4.9-1.module_el9.8.0+263+ff5e95cfALSA-2026:25052
AlmaLinux:8mysql-errmsg8.4.9-1.module_el8.10.0+4193+cbb8e728ALSA-2026:26180
AlmaLinux:8mysql-errmsg8.0.46-1.module_el8.10.0+4192+724bc664ALSA-2026:25919
AlmaLinux:9mysql-errmsg8.0.46-1.el9_8ALSA-2026:23332
AlmaLinux:9mysql-errmsg8.4.9-1.module_el9.8.0+263+ff5e95cfALSA-2026:25052
AlmaLinux:8mysql-libs8.4.9-1.module_el8.10.0+4193+cbb8e728ALSA-2026:26180
AlmaLinux:8mysql-libs8.0.46-1.module_el8.10.0+4192+724bc664ALSA-2026:25919
AlmaLinux:9mysql-libs8.0.46-1.el9_8ALSA-2026:23332
AlmaLinux:9mysql-libs8.4.9-1.module_el9.8.0+263+ff5e95cfALSA-2026:25052
AlmaLinux:8mysql-server8.4.9-1.module_el8.10.0+4193+cbb8e728ALSA-2026:26180
AlmaLinux:8mysql-server8.0.46-1.module_el8.10.0+4192+724bc664ALSA-2026:25919
AlmaLinux:9mysql-server8.4.9-1.module_el9.8.0+263+ff5e95cfALSA-2026:25052
AlmaLinux:9mysql-server8.0.46-1.el9_8ALSA-2026:23332
AlmaLinux:8mysql-test8.0.46-1.module_el8.10.0+4192+724bc664ALSA-2026:25919
AlmaLinux:8mysql-test8.4.9-1.module_el8.10.0+4193+cbb8e728ALSA-2026:26180
AlmaLinux:9mysql-test8.0.46-1.el9_8ALSA-2026:23332
AlmaLinux:9mysql-test8.4.9-1.module_el9.8.0+263+ff5e95cfALSA-2026:25052
AlmaLinux:8mysql-test-data8.4.9-1.module_el8.10.0+4193+cbb8e728ALSA-2026:26180
AlmaLinux:9mysql-test-data8.4.9-1.module_el9.8.0+263+ff5e95cfALSA-2026:25052
AlmaLinux:10mysql8.48.4.9-1.el10_2.alma.1ALSA-2026:20693
AlmaLinux:10mysql8.4-common8.4.9-1.el10_2.alma.1ALSA-2026:20693
AlmaLinux:10mysql8.4-devel8.4.9-1.el10_2.alma.1ALSA-2026:20693
AlmaLinux:10mysql8.4-errmsg8.4.9-1.el10_2.alma.1ALSA-2026:20693
AlmaLinux:10mysql8.4-libs8.4.9-1.el10_2.alma.1ALSA-2026:20693
AlmaLinux:10mysql8.4-server8.4.9-1.el10_2.alma.1ALSA-2026:20693
AlmaLinux:10mysql8.4-test8.4.9-1.el10_2.alma.1ALSA-2026:20693
AlmaLinux:10mysql8.4-test-data8.4.9-1.el10_2.alma.1ALSA-2026:20693
AlmaLinux:9perl-DBD-MySQL4.053-3.module_el9.8.0+235+a38ba90cALSA-2026:25052
AlmaLinux:9rapidjson-devel1.1.0-19.module_el9.6.0+152+8cbce00cALSA-2026:25052
AlmaLinux:9rapidjson-doc1.1.0-19.module_el9.6.0+152+8cbce00cALSA-2026:25052
Debian:12mariadb1:10.11.18-0+deb12u1DEBIAN-CVE-2026-34303
Debian:13mariadb1:11.8.6-0+deb13u1DEBIAN-CVE-2026-34303
Debian:14mariadb1:11.8.6-1DEBIAN-CVE-2026-34303
Rocky Linux:8mecab0:0.996-2.module+el8.10.0+2091+db4d14f6RLSA-2026:26180
Rocky Linux:8mecab0:0.996-2.module+el8.10.0+2091+db4d14f6RLSA-2026:25919
Rocky Linux:8mecab0:0.996-2.module+el8.10.0+1676+9b4b6e24RLSA-2026:25919
Rocky Linux:8mecab0:0.996-2.module+el8.10.0+1937+28fbbc83RLSA-2026:25919
Rocky Linux:8mecab0:0.996-2.module+el8.10.0+1676+9b4b6e24RLSA-2026:26180
Rocky Linux:8mecab0:0.996-2.module+el8.10.0+1937+28fbbc83RLSA-2026:26180
Rocky Linux:9mecab0:0.996-3.module+el9.8.0+40162+a76274f1.4RLSA-2026:25052
Rocky Linux:8mecab-ipadic0:2.7.0.20070801-17.module+el8.10.0+2091+db4d14f6RLSA-2026:26180
Rocky Linux:8mecab-ipadic0:2.7.0.20070801-17.module+el8.10.0+1937+28fbbc83RLSA-2026:25919
Rocky Linux:8mecab-ipadic0:2.7.0.20070801-17.module+el8.10.0+2091+db4d14f6RLSA-2026:25919
Rocky Linux:8mecab-ipadic0:2.7.0.20070801-17.module+el8.10.0+1937+28fbbc83RLSA-2026:26180
Rocky Linux:9mecab-ipadic0:2.7.0.20070801-24.module+el9.8.0+40162+a76274f1RLSA-2026:25052
Rocky Linux:9mysql0:8.0.46-1.el9_8.rocky.0.1RLSA-2026:23332
Rocky Linux:10mysql8.40:8.4.9-1.el10_2.rocky.0.1RLSA-2026:20693
Rocky Linux:9perl-DBD-MySQL0:4.053-3.module+el9.8.0+40162+a76274f1RLSA-2026:25052
Rocky Linux:9rapidjson0:1.1.0-19.module+el9.8.0+40162+a76274f1RLSA-2026:25052
Ubuntu:24.04:LTSmariadbno fix listedUBUNTU-CVE-2026-34303
Ubuntu:25.10mariadbno fix listedUBUNTU-CVE-2026-34303
Ubuntu:22.04:LTSmariadb-10.6no fix listedUBUNTU-CVE-2026-34303
Ubuntu:22.04:LTSmysql-8.08.0.46-0ubuntu0.22.04.2USN-8363-1
Ubuntu:22.04:LTSmysql-8.08.0.46-0ubuntu0.22.04.2UBUNTU-CVE-2026-34303
Ubuntu:24.04:LTSmysql-8.08.0.46-0ubuntu0.24.04.2USN-8363-1
Ubuntu:24.04:LTSmysql-8.08.0.46-0ubuntu0.24.04.2UBUNTU-CVE-2026-34303
Ubuntu:25.10mysql-8.48.4.9-0ubuntu0.25.10.1USN-8363-1
Ubuntu:25.10mysql-8.48.4.9-0ubuntu0.25.10.1UBUNTU-CVE-2026-34303
Ubuntu:26.04:LTSmysql-8.48.4.9-0ubuntu0.26.04.1UBUNTU-CVE-2026-34303
Ubuntu:26.04:LTSmysql-8.48.4.9-0ubuntu0.26.04.1USN-8363-1

Affected products (as reported)

VendorProductVersions
Oracle Corporation MySQL Server 8.0.0 – through 8.0.458.4.0 – through 8.4.89.0.0 – through 9.6.0

Weakness: CWE-400 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

References