CVE-2024-21126Network attack vector

Unauthenticated partial service interruption

Published Jul 16, 2024 · Updated Aug 29, 2024

Denial of service in Oracle Database Portable Clusterware 19.3 through 19.23 and 21.3 through 21.14 allows remote attackers to interrupt it via DNS. Oracle has not disclosed the flawed function or how crafted DNS traffic triggers the availability failure in Portable Clusterware. Network access over DNS is sufficient without authentication; successful exploitation causes a partial service interruption and does not directly disclose or alter data.

CVSS severity5.8
Medium
EPSS probability0.49%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Oracle Database Portable Clusterware 19.3 through 19.23 and 21.3 through 21.14 allows remote attackers to interrupt it via DNS. Oracle has not disclosed the flawed function or how crafted DNS traffic triggers the availability failure in Portable Clusterware. Network access over DNS is sufficient without authentication; successful exploitation causes a partial service interruption and does not directly disclose or alter data.

The record

CVE
CVE-2024-21126
Published
Jul 16, 2024
Updated
Aug 29, 2024
Vendor
Oracle
Product
Oracle Database
Classifications
CWE-400, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 16, 2024CVE publishedPublication date reported by the CVE source.
  2. Aug 29, 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=19.3 <=19.23
  2. Affected versionversion=21.3 <=21.14

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Oracle · Oracle Databaseversion=19.3 <=19.23; version=21.3 <=21.14
Oracle Corporation · Oracle Databaseversion=19.3 <=19.23; version=21.3 <=21.14

Published CVSS scores

5.8OracleCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L

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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
T1499.004Application or System Exploitation

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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