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CVE Record

CVE-2021-35629: 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

CVE-2021-35629 can let an already highly privileged network attacker crash or hang MySQL Server. The business impact is availability: affected databases may become unavailable, disrupting applications that depend on them. The sources identify MySQL Server 8.0.25 and prior as affected.

Executive priority

Treat this as a moderate-priority availability risk. Prioritize databases supporting critical applications, especially where privileged access is broadly distributed or where downtime has material business impact.

Technical view

The vulnerability is in Oracle MySQL Server, component Server: Optimizer. It is network reachable over multiple protocols, low complexity, requires high privileges, and needs no user interaction. Successful exploitation can cause a hang or frequently repeatable crash, resulting in complete denial of service. CVSS is 4.9 with availability impact only.

Likely exposure

Exposure is most relevant where MySQL Server 8.0.25 or prior is reachable by users or services with high database privileges over the network. Internet exposure is not required, but broad internal access increases operational risk.

Exploitation context

The provided sources do not state active exploitation, and the CVE is not listed as KEV in the bundle. Exploitation requires high privileges, which lowers likelihood, but a compromised or misused privileged account could still disrupt database availability.

Researcher notes

Evidence points to a denial-of-service issue in the optimizer with high privileges required. No confidentiality or integrity impact is indicated. The source bundle does not provide root-cause detail, exploit status, proof of concept, or a specific fixed version number.

Mitigation direction

  • Apply Oracle's October 2021 Critical Patch Update guidance for MySQL Server.
  • Move affected MySQL Server 8.0.25 or prior systems to a vendor-supported fixed release.
  • Restrict network access to MySQL services to trusted application hosts and administrators.
  • Review and reduce high-privilege MySQL accounts where operationally possible.
  • Check NetApp guidance if using NetApp products that package or depend on MySQL.

Validation and detection

  • Inventory MySQL Server instances and confirm whether any run 8.0.25 or prior.
  • Verify privileged MySQL accounts and identify which can connect over the network.
  • Review database availability logs for unexplained hangs or repeated crashes.
  • Confirm patch status against Oracle's October 2021 CPU documentation.
  • Validate compensating controls limiting network access to MySQL Server.
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-2021-35629 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-2021-35629Attack 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.