Skip to main content

Oracle MySQL EUVDEUVD-2026-106130

| CVE-2026-101729 MEDIUM
Improper Access Control (CWE-284)
2026-10-20 secalert_us@oracle.com GHSA-fcv9-47q3-p633
4.9
CVSS 3.1 · Vendor: oracle
View

Attack ChainAIDerived

Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain

  1. Access
    Obtain high-privileged DB credentials
  2. Delivery
    Connect via supported protocol
  3. Exploit
    Send crafted input to Replication component
  4. Execution
    Trigger hang or repeatable crash
  5. Impact
    Complete denial of service

Vulnerability Assessment

Weakness
CWE
OWASP Top 10:2025
A01:2025 - Broken Access Control
ASVS 5.0
V8 - Authorization Access control enforcement
MITRE ATT&CK

1 technique across 1 tactic: Defense Evasion

The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up.

Exploitation Conditions

Exploitation targets the MySQL Server/Cluster Replication component and requires a high-privileged database account (CVSS PR:H) reachable over the network via one of the supported protocols; no user interaction is needed. The limiting factors are substantial: the attacker must already possess elevated MySQL privileges, so this is effectively an authenticated, privileged-insider or post-credential-compromise condition rather than an anonymous remote attack. Affected deployments are MySQL Server 8.4.0-8.4.12, 9.7.0-9.7.3, 26.7.0-26.7.1 and MySQL Cluster 8.0.0-8.0.49, 8.4.0-8.4.12, 9.7.0-9.7.3, 26.7.0-26.7.1; environments that tightly restrict high-privilege accounts and network exposure to trusted hosts materially reduce exposure.

Impact

This is a moderate-severity, availability-only vulnerability (CVSS 3.1 base 4.9, vector AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H). The signals converge on a LOW real-world priority despite the network attack vector. The decisive limiting factor is PR:H: exploitation requires an already high-privileged account on the MySQL Server/Cluster, which dramatically narrows the realistic attacker population to insiders or an adversary who has already compromised privileged credentials. Impact is confined to availability (A:H, C:N/I:N) - a hang or repeatable crash (complete DOS) of the database, with no data confidentiality or integrity loss. No EPSS score, KEV listing, or POC was provided in the input, so there is no evidence of active exploitation or public exploit tooling. The 'easily exploitable' wording from Oracle (reflected in AC:L) is in tension with the high-privilege precondition - it is easy only for someone who already holds elevated database privileges. Net: a genuine but low-urgency patch item, not an emergency; prioritize via normal Oracle CPU patch cycles rather than out-of-band response. Note: CWE is listed as N/A and no EPSS/KEV data was supplied, so exploitation-probability signals are absent rather than low.

Exploit ScenarioDerived

An attacker who already holds a high-privileged MySQL account (or has compromised such credentials) connects over the network via one of the supported protocols and issues crafted input to the Replication component, causing the server to hang or repeatedly crash, producing a complete denial of service of the MySQL Server or Cluster. No public exploit code was identified in the provided data, and no user interaction is required. The attack yields only downtime - no data theft or modification.

This Month Plan within 30 days. Why: MEDIUM severity (CVSS 4.0-6.9).
No patch listed yet 0.4% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAIv1 – Oct 21, 2026

Denial of service in Oracle MySQL Server and MySQL Cluster (Server: Replication component) lets a high-privileged, network-reachable database account hang or repeatedly crash the service, affecting MySQL Server 8.4.0-8.4.12, 9.7.0-9.7.3 and 26.7.0-26.7.1 as well as MySQL Cluster 8.0.0-8.0.49, 8.4.0-8.4.12, 9.7.0-9.7.3 and 26.7.0-26.7.1. The CVSS 3.1 base score is 4.9 (AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H), so impact is availability-only and the attack path is gated behind elevated MySQL privileges - this is a privileged-insider or post-compromise persistence-of-disruption scenario rather than an anonymous remote attack. There is no CISA KEV listing and no public exploit code identified at time of analysis; Oracle addresses the flaw in its October 2026 Critical Patch Update.

RemediationAI

Patch available per vendor advisory: apply the Oracle Critical Patch Update for October 2026 (https://www.oracle.com/security-alerts/cpuoct2026.html) and move each installation past the affected upper bounds - later than 8.4.12 and 9.7.3 for MySQL Server, and later than 8.0.49, 8.4.12, 9.7.3 and 26.7.1 for MySQL Cluster; confirm the exact replacement build in the CPU documentation before upgrading, since the advisory rather than this analysis is the source of truth for version numbers. Because exploitation requires a high-privileged account (PR:H), the most effective interim control is privilege reduction: audit and revoke replication-related grants (REPLICATION SLAVE, REPLICATION CLIENT, and broad SUPER or Cluster admin rights) from any account that does not strictly need them, and remove anonymous or shared administrative logins - the trade-off is that legitimate replication and failover tooling may need re-granting with narrower scopes. Complement this with network restriction: bind management and replication ports to trusted host ranges via firewall rules, MySQL account host patterns, or TLS client certificates, accepting the added operational overhead of maintaining allowlists. Where a maintenance window allows, restart a crashed node under supervised conditions rather than relying on automated restart loops, which can convert a single crash into sustained unavailability. No CISA KEV entry or public exploit code was identified at time of analysis, so there is no evidence of active exploitation to drive emergency out-of-band patching.

Affected VersionsENISA

MySQL Server 8.4.0-8.4.12
MySQL Cluster 9.7.0-9.7.3
MySQL Server 9.7.0-9.7.3
MySQL Cluster 8.0.0-8.0.49
MySQL Cluster 8.4.0-8.4.12
MySQL Cluster 26.7.0-26.7.1
MySQL Server 26.7.0-26.7.1

Affected Packages

euvd mysql_cluster no fix
euvd mysql_server no fix

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 2 packages in euvd

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

The flaw sits in the Replication subsystem of Oracle MySQL, the component that implements binary-log based replication between a source and its replicas as well as group replication and MySQL Cluster (NDB) replication channels. According to the CVSS vector CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H, the attack is launched over the network with low complexity and no user interaction, but requires high privileges on the database server; scope is unchanged and only availability is impacted, meaning the attacker can force a hang or a frequently repeatable crash of the server or cluster rather than read or modify data. No CWE identifier was supplied by the reporter, so the precise root-cause class (for example improper input validation, an uncontrolled resource-consumption condition, or a race in replication-state handling) cannot be confirmed from the available data; the practical effect is that malformed or adversarial replication traffic accepted from a highly privileged session destabilizes the process. Because the Replication component is present in both the classic MySQL Server package and MySQL Cluster (NDB), the exposure surface spans standalone primary/replica topologies as well as clustered deployments, and any monitoring or failover automation that restarts crashed nodes can amplify the operational impact of repeated crashes.

Know when the next one hits your stack

  • Watch products and get an email when something new is published
  • Check this CVE against your own stack and servers
  • Exploit and PoC references, threat intelligence from 22 sources

No credit card · 7-day full trial

Severity by source

Vendor (oracle) PRIMARY 4.9 MEDIUM
AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
vuln.today AI 4.9 MEDIUM

Network-reachable (AV:N) and low complexity (AC:L) per Oracle, but requires a high-privileged DB account (PR:H); impact is availability-only (A:H), with no confidentiality or integrity effect.

3.1 AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
4.0 AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Red Hat 4.9 MEDIUM

Primary rating from Vendor (oracle).

CVSS VectorVendor: oracle

Attack Vector
Network
Attack Complexity
Low
Privileges Required
High
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

DescriptionCVE.org

Vulnerability in the MySQL Server, MySQL Cluster product of Oracle MySQL (component: Server: Replication). Supported versions that are affected are MySQL Server: 8.4.0-8.4.12, 9.7.0-9.7.3, 26.7.0-26.7.1; MySQL Cluster: 8.0.0-8.0.49, 8.4.0-8.4.12, 9.7.0-9.7.3 and 26.7.0-26.7.1. Easily exploitable vulnerability allows high privileged attacker with network access via multiple protocols to compromise MySQL Server, MySQL Cluster. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server, MySQL Cluster. 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).

Threat Intelligence Overview

EPSS Score
0.4%
Top 65% exploitable
Prevalence
Ubiquitous
MySQL is among the most widely deployed database servers worldwide
Data Quality
4 sources
Confidence: Medium

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity MEDIUM
CISA KEV No
Public POC No
EPSS 0.4%
Patch available No
Active threat No
Deciding rule
MEDIUM severity (CVSS 4.0-6.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Scheduled
Exploitation· derived
None
System Exposure· derived
Open
Automatable· derived
No
Human Impact· derived
Medium

Priority Score

24
Low Medium High Critical
KEV: 0
EPSS: 0
CVSS: +24
PoC: 0
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.

Vendor StatusVendor

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy