CVE-2026-21949
published 2026-01-20CVE-2026-21949: 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…
PriorityP336medium6.5CVSS 3.1
AVNACLPRLUINSUCNINAH
EPSS
0.32%
23.7th percentile
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).
Affected
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | mysql-8.0 | — | — |
| oracle | mysql_server | 9.0.0 – 9.5.0 | — |
| oracle_corporation | mysql_server | 9.0.0 – 9.5.0 | — |
CVSS provenance
nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv6.5MEDIUM
vendor_debian6.5LOW
vendor_oracle6.5MEDIUM
vendor_redhat6.5MEDIUM
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Red Hat
mysql: Optimizer unspecified vulnerability (CPU Jan 2026)
vendor_redhat·2026-01-20·CVSS 6.5
CVE-2026-21949 [MEDIUM] mysql: Optimizer unspecified vulnerability (CPU Jan 2026)
mysql: Optimizer unspecified vulnerability (CPU Jan 2026)
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).
Oracle CPU describes the issue as following: 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 e
Oracle
Oracle Oracle MySQL Risk Matrix: Server: Optimizer — CVE-2026-21949
vendor_oracle·2026-01-15·CVSS 6.5
CVE-2026-21949 [MEDIUM] Oracle Oracle MySQL Risk Matrix: Server: Optimizer — CVE-2026-21949
Oracle Oracle MySQL Risk Matrix: Server: Optimizer vulnerability
CVE: CVE-2026-21949
CVSS: 6.5
Protocol: MySQL Protocol
Remote exploit: No
Affected versions: Network
Advisory: cpujan2026 (JAN 2026)
Debian
CVE-2026-21949: mysql-8.0 - Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Op...
vendor_debian·2026·CVSS 6.5
CVE-2026-21949 [MEDIUM] CVE-2026-21949: mysql-8.0 - Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Op...
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).
Scope: local
sid: resolved
GHSA
GHSA-5874-2h56-xqh9: Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer)
ghsa_unreviewed·2026-01-21
CVE-2026-21949 [MEDIUM] CWE-400 GHSA-5874-2h56-xqh9: Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer)
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).
OSV
CVE-2026-21949: Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer)
osv·2026-01-20·CVSS 6.5
CVE-2026-21949 [MEDIUM] CVE-2026-21949: Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer)
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).
No detection rules found.
No public exploits indexed.
2026-01-20
Published