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CVE Record

CVE-2021-2171: Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Replication).

Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Replication). Supported versions that are affected are 5.7.33 and prior and 8.0.23 and prior. Difficult to exploit 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 4.4 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H).

MediumCVSS 4.4Not KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

CVE-2021-2171 is a MySQL Server replication-related flaw that can let a highly privileged network attacker crash or hang the database. It is not described as data theft or data alteration. The business risk is service disruption for systems relying on affected MySQL versions.

Executive priority

Treat this as a planned remediation item unless the affected database supports critical services or privileged access is broadly distributed. Prioritize hardening access and patching during normal database maintenance windows.

Technical view

Oracle lists MySQL Server 5.7.33 and prior, and 8.0.23 and prior, as affected. The CVSS vector requires network access, high privileges, no user interaction, high attack complexity, and causes high availability impact only. The affected component is Server: Replication.

Likely exposure

Exposure is most likely where affected MySQL Server versions are reachable over a network by administrative or highly privileged accounts. Internet exposure is less central than privileged access control, but network-reachable database services still increase operational risk.

Exploitation context

The provided sources do not show CISA KEV listing or active exploitation. The vulnerability is described as difficult to exploit and requiring high privileges, which lowers broad exploitation likelihood but does not remove insider, compromised-admin, or misconfigured-access risk.

Researcher notes

No CWE is provided in the source bundle. The available evidence identifies impact and version ranges but does not provide root-cause detail, proof-of-concept status, or exploit indicators. Avoid assuming confidentiality or integrity impact because CVSS states none.

Mitigation direction

  • Upgrade affected MySQL Server versions using Oracle CPU guidance or later vendor-supported packages.
  • Apply relevant Fedora or NetApp updates where those distributions or products include MySQL exposure.
  • Restrict MySQL network access to trusted hosts and administrative networks only.
  • Review and minimize highly privileged MySQL accounts with network access.
  • Monitor vendor advisories for environment-specific remediation details.

Validation and detection

  • Inventory MySQL Server versions and flag 5.7.33 or earlier and 8.0.23 or earlier.
  • Confirm whether affected servers are reachable over network paths by privileged accounts.
  • Check whether downstream Fedora or NetApp advisories apply to deployed systems.
  • Review database availability logs for unexplained hangs or repeatable crashes.
  • Verify upgraded systems are outside the affected version ranges.
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

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CVE-2021-2171 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
4.4 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:H/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
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
4.4CVSS 3.1MediumCVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H0.73.6Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

4.4Medium
CVSS 3.1 vector shape for CVE-2021-2171Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:H/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 Server5.7.33 and prior, 8.0.23 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.