CVE-2021-35558Network attack vector

Authenticated service interruption via undisclosed Core RDBMS flaw

Published Oct 20, 2021 · Updated Sep 25, 2024

Denial of service in Oracle Database 12.1.0.2, 12.2.0.1, 19c, and 21c allows remote authenticated users to disrupt Core RDBMS. Oracle has not published the faulty Core RDBMS operation or the input that triggers the availability loss. Exploitation requires network access through Oracle Net and a low-privileged account with Create Table privilege, and the documented consequence is partial service interruption.

CVSS severity4.3
Medium
EPSS probability0.83%
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 12.1.0.2, 12.2.0.1, 19c, and 21c allows remote authenticated users to disrupt Core RDBMS. Oracle has not published the faulty Core RDBMS operation or the input that triggers the availability loss. Exploitation requires network access through Oracle Net and a low-privileged account with Create Table privilege, and the documented consequence is partial service interruption.

The record

CVE
CVE-2021-35558
Published
Oct 20, 2021
Updated
Sep 25, 2024
Vendor
Oracle Corporation
Product
Oracle Database
Classifications
T1499
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 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=12.1.0.2
  2. Affected versionversion=12.2.0.1
  3. Affected versionversion=19c
  4. Affected versionversion=21c

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Oracle Corporation · Oracle Databaseversion=12.1.0.2; version=12.2.0.1; version=19c; version=21c

Published CVSS scores

4.3Oracle CorporationCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
4.0NIST NVDAV:N/AC:L/Au:S/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.

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
Privilegesauthenticated
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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