VulnerabilityPublished 21 Oct 2025

CVE-2025-53040: Oracle MySQL Server · Uncontrolled Resource Consumption

Affects Oracle MySQL ServerSource CVE Database V5

Not known to be exploited · CVSS 4.9 Medium.

Data as of 26 Oct 2026, 10:12 UTC

CVSS 3.1 base score

4.9Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.5% chance of exploitation in 30 days – higher than 47% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H

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

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: High: The attacker is authorized with (i.e., requires) privileges that provide significant (e.g., administrative) control over the vulnerable component that could affect component-wide settings and files.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 21 Oct 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Mavencom.oracle/mysql-server`pkg:maven/com.oracle/mysql-server`Other threats	Affected =8.0.0 =8.4.0 =9.0.0	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Restrict network access to MySQL Server instances to trusted and authenticated users only, employing network segmentation and firewall rules to limit exposure.
Enforce the principle of least privilege rigorously, ensuring that only necessary users have high-level privileges required to exploit this vulnerability.
Monitor MySQL server logs and system metrics for signs of abnormal hangs, crashes, or resource exhaustion indicative of attempted exploitation.
Implement robust incident response procedures to quickly isolate and recover affected MySQL instances in case of DoS events.
Stay updated with Oracle security advisories and apply patches or updates promptly once they become available for this vulnerability.
Consider deploying MySQL in high-availability configurations with failover capabilities to minimize downtime impact.
Conduct regular security audits and vulnerability assessments focusing on privilege management and network exposure of database servers.
Use intrusion detection/prevention systems (IDS/IPS) to detect anomalous traffic patterns targeting MySQL protocols.
For cloud environments, leverage provider-specific security controls to restrict administrative access and monitor for suspicious activities.
Educate database administrators and security teams about this vulnerability and the importance of maintaining strict access controls.

Description

Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.0-8.0.43, 8.4.0-8.4.6 and 9.0.0-9.4.0. 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).

Impact

For European organizations, the primary impact of CVE-2025-53040 is the potential for denial-of-service attacks against MySQL Server instances, which can cause service outages and disrupt business operations. Industries heavily reliant on database availability, such as finance, telecommunications, healthcare, and e-commerce, could experience operational interruptions, loss of productivity, and reputational damage. Since the vulnerability requires high privileges, the risk is elevated in environments where internal threat actors or compromised administrators exist. Cloud service providers and managed service providers hosting MySQL databases for European clients may also be at risk, potentially affecting multiple downstream customers. The lack of confidentiality or integrity impact reduces the risk of data breaches but does not diminish the operational risks associated with service unavailability. Additionally, regulatory frameworks like GDPR emphasize availability as part of data protection, so prolonged outages could have compliance implications. Organizations with MySQL servers exposed to untrusted networks or insufficiently segmented internal networks face higher exposure. The absence of known exploits currently provides a window for proactive mitigation but also warrants vigilance for emerging threats.

CWE-400Uncontrolled Resource Consumption (opens in a new tab)
Class weaknessLikelihood of exploit: High
The product does not properly control the allocation and maintenance of a limited resource.
MITRE discourages mapping vulnerabilities to this broad entry; the root cause is usually a more specific weakness.
Architecture and Design
Design throttling mechanisms into the system architecture. The best protection is to limit the amount of resources that an unauthorized user can cause to be expended. A strong authentication and access control model will help prevent such attacks from occurring in the first place.
Architecture and Design
Mitigation of resource exhaustion attacks requires that the target system either: recognizes the attack and denies that user further access for a given amount of time, or; uniformly throttles all requests in order to make it more difficult to consume resources more quickly than they can again be freed.
Architecture and Design
Ensure that protocols have specific limits of scale placed on them.
OWASP Cheat Sheets
File Upload (opens in a new tab)
OWASP ASVS 4.0.3
V12.1.1 (opens in a new tab)
Attack patterns
XML Ping of the Death (opens in a new tab)
Regular Expression Exponential Blowup (opens in a new tab)
Sustained Client Engagement (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

oracle.com/security-alerts/cpuoct2025.html (opens in a new tab)

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 28 Oct 2025, 22:03 UTC

WeaknessesCWE-400

Technical details

References

Community reviews

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