CVE-2026-83349Network attack vector

Unauthenticated listener hang or repeatable crash

Published Sep 15, 2026 · Updated Sep 15, 2026

Oracle Database Net Services allows remote attackers to hang or repeatedly crash affected listeners through unauthenticated Oracle Net traffic. Oracle has not published the parsing or request-processing error within Oracle Net Services that mishandles the traffic. Network reachability is sufficient; affected 19.3 through 19.32, 21.3 through 21.23, and 23.4.0 through 23.26.3 installations can lose listener availability without data disclosure or modification.

CVSS severity7.5
High
EPSS probability0.46%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Oracle Database Net Services allows remote attackers to hang or repeatedly crash affected listeners through unauthenticated Oracle Net traffic. Oracle has not published the parsing or request-processing error within Oracle Net Services that mishandles the traffic. Network reachability is sufficient; affected 19.3 through 19.32, 21.3 through 21.23, and 23.4.0 through 23.26.3 installations can lose listener availability without data disclosure or modification.

The record

CVE
CVE-2026-83349
Published
Sep 15, 2026
Updated
Sep 15, 2026
Vendor
Oracle Corporation
Product
Oracle Database
Classifications
T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 15, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 15, 2026Record 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 <=19.32
  2. Affected versionversion=21.3 <=21.23
  3. Affected versionversion=23.4.0 <=23.26.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Oracle Corporation · Oracle Databaseversion=19.3 <=19.32; version=21.3 <=21.23; version=23.4.0 <=23.26.3

Published CVSS scores

7.5Oracle CorporationCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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
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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