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CVE Record

CVE-2021-2481: 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 8.0.26 and prior. 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).

MediumCVSS 6.5Not KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

This MySQL Server flaw can let a low-privileged network user crash or hang the database service. The main business risk is downtime, not data theft or data tampering. Systems running MySQL Server 8.0.26 or earlier should be reviewed and updated according to Oracle and downstream vendor guidance.

Executive priority

Treat this as a medium-priority availability risk. Prioritize systems supporting customer-facing services, revenue operations, or shared platforms where database downtime would create visible business disruption.

Technical view

CVE-2021-2481 affects Oracle MySQL Server Optimizer in supported versions 8.0.26 and prior. It is network reachable, low complexity, requires low privileges, and needs no user interaction. Successful exploitation can cause a complete denial of service through a hang or repeatable crash. CVSS 3.1 score is 6.5.

Likely exposure

Exposure is most relevant where MySQL Server 8.0.26 or earlier accepts network connections from users or services with database credentials. Internet-facing or broadly reachable database ports increase operational risk.

Exploitation context

The provided sources do not show CISA KEV listing or confirmed active exploitation. The vulnerability is described as easily exploitable by a low-privileged attacker with network access, making credentialed network reachability the key concern.

Researcher notes

The source bundle identifies component, version range, CVSS vector, and availability-only impact, but does not provide CWE, root-cause detail, exploit artifacts, or a specific fixed version. Avoid claiming exploitation beyond the provided evidence.

Mitigation direction

  • Inventory MySQL Server instances and identify versions 8.0.26 or earlier.
  • Apply Oracle October 2021 CPU guidance or later supported vendor updates.
  • Follow NetApp guidance where embedded or packaged MySQL is present.
  • Apply Fedora package advisories where Fedora-distributed MySQL packages are used.
  • Restrict MySQL network access to trusted clients and service accounts.
  • Monitor database availability until affected systems are updated.

Validation and detection

  • Confirm every MySQL Server instance version and build source.
  • Check whether any NetApp or Fedora-managed systems include affected MySQL packages.
  • Verify Oracle or downstream vendor updates are installed successfully.
  • Review MySQL logs and monitoring for unexplained hangs or repeatable crashes.
  • Confirm only authorized users can reach MySQL listener ports.
Prepared
Confidence
high
Sources
7

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.

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CVE-2021-2481 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
6.5 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:L/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
6Source 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
6.5CVSS 3.1MediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H2.83.6Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

6.5Medium
CVSS 3.1 vector shape for CVE-2021-2481Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:L/PR:L/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 Server8.0.26 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.