Oracle MySQL Server up to 8.0.45/8.4.8/9.6.0 Optimizer denial of service

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$0-$5k0.00

Summaryinfo

A vulnerability was found in Oracle MySQL Server up to 8.0.45/8.4.8/9.6.0. It has been declared as problematic. This impacts an unknown function of the component Optimizer. The manipulation results in denial of service. This vulnerability is identified as CVE-2026-34303. The attack can be executed remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as problematic has been found in Oracle MySQL Server up to 8.0.45/8.4.8/9.6.0. Affected is some unknown processing of the component Optimizer. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability. CVE summarizes:

Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.0-8.0.45, 8.4.0-8.4.8 and 9.0.0-9.6.0. Easily exploitable vulnerability allows low 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 6.5 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H).

The advisory is available at oracle.com. This vulnerability is traded as CVE-2026-34303 since 03/26/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 04/22/2026). This vulnerability is assigned to T1499 by the MITRE ATT&CK project.

Upgrading eliminates this vulnerability.

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Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (oracle): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Timelineinfo

03/26/2026 CVE reserved
04/22/2026 +26 days Advisory disclosed
04/22/2026 +0 days VulDB entry created
04/22/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: oracle.com

Advisory: oracle.com
Status: Confirmed

CVE: CVE-2026-34303 (🔒)
GCVE (CVE): GCVE-0-2026-34303
GCVE (VulDB): GCVE-100-358686

Entryinfo

Created: 04/22/2026 06:54
Changes: 04/22/2026 06:54 (64)
Complete: 🔍
Cache ID: 216::103

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