CVE-2025-21555Network attack vector

High-privilege data modification and service interruption

Published Jan 21, 2025 · Updated Nov 3, 2025

InnoDB flaw in Oracle MySQL Server 8.0.40 and earlier, 8.4.3 and earlier, and 9.1.0 and earlier allows remote authenticated users to alter data. Oracle has not disclosed the affected InnoDB code path or the operation it performs incorrectly on attacker-controlled input. Exploitation requires a highly privileged MySQL account with network access and can update, insert, or delete some accessible data or cause a hang or repeatable crash.

CVSS severity5.5
Medium
EPSS probability0.73%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

InnoDB flaw in Oracle MySQL Server 8.0.40 and earlier, 8.4.3 and earlier, and 9.1.0 and earlier allows remote authenticated users to alter data. Oracle has not disclosed the affected InnoDB code path or the operation it performs incorrectly on attacker-controlled input. Exploitation requires a highly privileged MySQL account with network access and can update, insert, or delete some accessible data or cause a hang or repeatable crash.

The record

CVE
CVE-2025-21555
Published
Jan 21, 2025
Updated
Nov 3, 2025
Vendor
Oracle Corporation
Product
MySQL Server
Classifications
T1565, T1499
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jan 21, 2025CVE publishedPublication date reported by the CVE source.
  2. Nov 3, 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=* <=8.0.40
  2. Affected versionversion=* <=8.4.3
  3. Affected versionversion=* <=9.1.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Oracle Corporation · MySQL Serverversion=* <=8.0.40; version=* <=8.4.3; version=* <=9.1.0

Published CVSS scores

5.5Oracle CorporationCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1565Data Manipulation
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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