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CVE Record

CVE-2021-2437: 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 flaw in Oracle MySQL Server’s optimizer. An attacker who already has high MySQL privileges and network access can make the database hang or repeatedly crash. It does not expose data or allow data changes in the cited CVSS impact, but it can interrupt business systems that depend on affected MySQL versions.

Executive priority

Treat as a planned remediation item unless affected databases support critical services or privileged account security is weak. The business risk is outage, not data theft, but repeated database crashes can still disrupt operations.

Technical view

CVE-2021-2437 affects MySQL Server 8.0.25 and prior in the Server: Optimizer component. CVSS 3.1 is 4.9 with AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H. The vulnerability is remotely reachable over multiple protocols but requires high privileges, with impact limited to complete availability loss.

Likely exposure

Exposure is mainly databases running Oracle MySQL Server 8.0.25 or earlier where high-privilege accounts can connect over the network. Risk is lower where privileged database access is tightly restricted and monitored.

Exploitation context

The provided sources do not report active exploitation, and the CVE is not listed as KEV. Exploitation requires high privileges, so insider misuse, compromised admin credentials, or over-permissive service accounts are the most relevant scenarios.

Researcher notes

The bundle identifies the affected component, version range, CVSS vector, and availability-only impact, but not root cause details, CWE, exploit mechanics, or exact fixed version. Avoid assuming broader products beyond Oracle MySQL Server and cited vendor advisories.

Mitigation direction

  • Identify MySQL Server instances running 8.0.25 or earlier.
  • Review Oracle July 2021 CPU guidance and apply applicable MySQL updates.
  • Check NetApp guidance if MySQL is embedded in NetApp-managed products.
  • Restrict high-privilege MySQL accounts to trusted networks and users.
  • Monitor privileged database sessions for unusual crash or hang patterns.

Validation and detection

  • Inventory MySQL versions and confirm whether any are 8.0.25 or earlier.
  • Review database account privileges and network access paths.
  • Check service logs for repeated MySQL crashes or unexplained hangs.
  • Confirm vendor advisories are tracked for Oracle and relevant appliance vendors.
Prepared
Confidence
medium
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-2021-2437 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-2021-2437Attack 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.