CVE-2023-21950Network attack vector

Privileged denial of service via replication traffic

Published Jul 18, 2023 · Updated Feb 13, 2025

Denial of service in Oracle MySQL Server 8.0.27 and earlier allows remote authenticated users with high privileges to hang or crash the server. Oracle has disclosed only the Server: Replication locus, not the flawed operation or protocol input that triggers it. Successful exploitation interrupts database availability through a hang or repeatable crash and requires high privileges plus network access.

CVSS severity4.9
Medium
EPSS probability1.00%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Oracle MySQL Server 8.0.27 and earlier allows remote authenticated users with high privileges to hang or crash the server. Oracle has disclosed only the Server: Replication locus, not the flawed operation or protocol input that triggers it. Successful exploitation interrupts database availability through a hang or repeatable crash and requires high privileges plus network access.

The record

CVE
CVE-2023-21950
Published
Jul 18, 2023
Updated
Feb 13, 2025
Vendor
Oracle Corporation
Product
MySQL Server
Classifications
T1499
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jul 18, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=* <=8.0.27

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Oracle Corporation · MySQL Serverversion=* <=8.0.27

Published CVSS scores

4.9Oracle CorporationCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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