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CVE Record

CVE-2021-2418: 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 8.0.25 and prior. 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 hang or frequently repeatable crash (complete DOS) of MySQL Server. CVSS 3.1 Base Score 4.9 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).

MediumCVSS 4.9Not KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

This is a denial-of-service weakness in Oracle MySQL Server’s optimizer. A high-privileged attacker who can reach MySQL over the network could cause the database server to hang or crash repeatedly. The issue affects MySQL Server 8.0.25 and earlier. Business impact is service interruption, not data theft or tampering based on provided sources.

Executive priority

Treat as a medium-priority availability risk. It does not indicate data compromise, but a privileged attacker could repeatedly crash a database service. Prioritize internet-reachable, business-critical, or shared MySQL environments and any products covered by downstream vendor advisories.

Technical view

CVE-2021-2418 affects Oracle MySQL Server, component Server: Optimizer. Oracle lists supported affected versions as 8.0.25 and prior, CVSS 3.1 score 4.9, vector AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H. The stated outcome is complete availability loss through hang or repeatable crash.

Likely exposure

Exposure is most likely where MySQL Server 8.0.25 or earlier is reachable by users or services with high database privileges. Internet exposure increases operational risk, but privileges are required. NetApp’s advisory indicates downstream product users should also check vendor-specific exposure guidance.

Exploitation context

The provided sources do not show active exploitation, and this CVE is not listed as KEV in the bundle. Exploitation requires high privileges and network access via supported MySQL protocols. The practical concern is disruption of database availability by an already-privileged actor.

Researcher notes

Key constraints are PR:H and availability-only impact. The source bundle does not provide exploit details, root cause mechanics, CWE classification, or a named fixed version. Use Oracle’s CPU and vendor advisories for precise remediation mapping rather than assuming product-specific fixes.

Mitigation direction

  • Identify all MySQL Server deployments at version 8.0.25 or earlier.
  • Apply Oracle July 2021 CPU guidance or current Oracle MySQL security updates.
  • Restrict MySQL network access to trusted application and administration paths.
  • Review and reduce high-privilege MySQL accounts to operational minimums.
  • Check NetApp advisory guidance for affected downstream products.

Validation and detection

  • Inventory MySQL Server versions across hosts, containers, and managed images.
  • Confirm whether any deployment reports MySQL Server 8.0.25 or earlier.
  • Review firewall, security group, and listener exposure for MySQL ports.
  • Audit accounts with high MySQL privileges and recent activity.
  • Check vendor advisories for bundled MySQL in appliances or platforms.
Prepared
Confidence
high
Sources
4

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

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CVE-2021-2418 mapping review

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

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Vulnerability profileCVE Program record
Severity
Medium
CVSS
4.9 (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:H

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
3Source 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
4.9CVSS 3.1MediumCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H1.23.6Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

4.9Medium
CVSS 3.1 vector shape for CVE-2021-2418Attack 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:H

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 Server8.0.25 and priorListed
Weakness

CWE details

No CWE listed

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