LiveActive security incident?Get immediate response
CVE Record

CVE-2026-21965: Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Pluggable Auth).

Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Pluggable Auth). Supported versions that are affected are 9.0.0-9.5.0. 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 partial denial of service (partial DOS) of MySQL Server. CVSS 3.1 Base Score 2.7 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L).

LowCVSS 2.7Not KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysislow

Security readout for executives and security teams

Plain-English summary

CVE-2026-21965 is a low-severity Oracle MySQL Server issue in pluggable authentication. A high-privileged attacker with network access could trigger a partial denial of service. Business urgency is limited unless affected MySQL 9.x systems are internet-exposed, shared across critical services, or administered by many privileged users.

Executive priority

Treat as routine patch management unless affected MySQL systems support critical services or have broad privileged access. Prioritize confirmation in asset inventories, then patch during the next appropriate maintenance window following Oracle guidance.

Technical view

Oracle describes an easily exploitable vulnerability in MySQL Server, component Server: Pluggable Auth. Affected supported versions are listed as 9.0.0 through 9.5.0. The CVSS 3.1 score is 2.7 with AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L, indicating network reachability but requiring high privileges and causing only limited availability impact.

Likely exposure

Exposure is limited to Oracle MySQL Server versions 9.0.0 through 9.5.0 where high-privileged users can reach the server over supported network protocols. Systems with restricted administrative access and network segmentation have lower practical risk.

Exploitation context

The provided sources do not report active exploitation, and the CVE is not marked as CISA KEV. The attacker must already have high privileges and network access. Impact is partial denial of service, not data theft or privilege escalation according to the CVSS metrics.

Researcher notes

Public details are sparse. The CVE identifies the component and CVSS characteristics but does not provide a CWE, root cause, or exploit mechanics. Note the source bundle’s structured affected entry lists 9.0.0, while the description states 9.0.0-9.5.0; use Oracle’s advisory as authoritative.

Mitigation direction

  • Review Oracle’s January 2026 Critical Patch Update for MySQL Server guidance.
  • Upgrade or patch affected MySQL Server 9.0.0-9.5.0 deployments per Oracle instructions.
  • Restrict privileged MySQL administrative access to trusted networks and users.
  • Monitor MySQL availability and authentication-related errors on affected systems.

Validation and detection

  • Inventory MySQL Server versions and identify 9.0.0 through 9.5.0 deployments.
  • Confirm whether Oracle January 2026 CPU fixes are applied.
  • Review privileged MySQL accounts and network paths to database servers.
  • Check monitoring for unusual partial service interruptions or authentication component errors.
Prepared
Confidence
medium
Sources
3

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cve · low confidence lookup

CVE-2026-21965 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Low
CVSS
2.7 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
0Timeline events
0ADP providers
2Source links

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
2.7CVSS 3.1LowCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L1.21.4Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

2.7Low
CVSS 3.1 vector shape for CVE-2026-21965Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
Oracle CorporationMySQL Server9.0.0Listed
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.