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 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).
Conclusion & alert: CVE-2026-21968 is rated Low Risk (32.2/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.06%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-03-21 | 0.04% | 0.06% | +0.02% |
| 2 | 2026-01-21 | — | 0.04% | — |
Full EPSS history (2 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 6.5 | 3.1 | MEDIUM |
|
2.8 | 3.6 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2026-21968 not yet assigned priority: Debian including 2 source packages (mariadb, mysql-8.0), 5 status rows across 4 suites (bookworm, forky, sid, trixie): resolved 4, open 1. | https://security-tracker.debian.org/tracker/CVE-2026-21968 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2026-21968 |
suse
|
medium | CVE-2026-21968 severity moderate: SUSE including 12 source package names (libmariadbd-devel, libmariadbd19, …), 88 product×package rows across 16 product lines (SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS, SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS, … (16 product lines)): Known Not Affected 81, Will Not Fix 7. | https://www.suse.com/security/cve/CVE-2026-21968/ |
ubuntu
|
medium | CVE-2026-21968 medium priority: Ubuntu including 11 source packages (mariadb, mariadb-10.0, …), 53 status rows across 8 suites (bionic, focal, jammy, noble, questing, trusty, upstream, xenial): DNE 27, needs-triage 15, released 7, ignored 4. | https://ubuntu.com/security/CVE-2026-21968 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| oracle | mysql_server | >= 8.0.0, <= 8.0.44 | cpe:2.3:a:oracle:mysql_server:*:*:*:*:*:*:*:* |
| oracle | mysql_server | >= 8.4.0, <= 8.4.7 | cpe:2.3:a:oracle:mysql_server:*:*:*:*:*:*:*:* |
| oracle | mysql_server | >= 9.0.0, <= 9.5.0 | cpe:2.3:a:oracle:mysql_server:*:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://www.oracle.com/security-alerts/cpujan2026.html | Vendor Advisory |