CVE-2021-2429Network attack vector

Service crash via InnoDB heap buffer overflow

Published Jul 20, 2021 · Updated Sep 25, 2024

Heap-based buffer overflow in MySQL Server 8.0.25 and earlier allows remote attackers to crash the service through the MySQL protocol. InnoDB command processing copies user-supplied data into a heap buffer without first validating its length. No authentication is required, but high-complexity conditions must be met; the documented outcome is a hang or repeatable crash.

CVSS severity5.9
Medium
EPSS probability41.48%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Heap-based buffer overflow in MySQL Server 8.0.25 and earlier allows remote attackers to crash the service through the MySQL protocol. InnoDB command processing copies user-supplied data into a heap buffer without first validating its length. No authentication is required, but high-complexity conditions must be met; the documented outcome is a hang or repeatable crash.

The record

CVE
CVE-2021-2429
Published
Jul 20, 2021
Updated
Sep 25, 2024
Vendor
Oracle Corporation
Product
MySQL Server
Classifications
T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 20, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 25, 2024Record 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=8.0.25 and prior

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Oracle Corporation · MySQL Serverversion=8.0.25 and prior

Published CVSS scores

5.9OracleCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:N/A:P

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

Weakness, pattern, technique

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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