CVE-2023-27555

Server crash via unfenced DRDA client affinity

Published Apr 28, 2023 · Updated Feb 13, 2025

Denial of service in IBM Db2 11.5 allows local users to crash the server through ACR client affinity on unfenced DRDA wrappers. IBM identifies the affected locus as ACR client-affinity processing for unfenced DRDA federation wrappers but does not disclose the faulty operation. The crash requires the high-complexity, unsupported combination of client affinity with an unfenced federation wrapper and interrupts database availability.

CVSS severity5.1
Medium
EPSS probability0.60%
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 IBM Db2 11.5 allows local users to crash the server through ACR client affinity on unfenced DRDA wrappers. IBM identifies the affected locus as ACR client-affinity processing for unfenced DRDA federation wrappers but does not disclose the faulty operation. The crash requires the high-complexity, unsupported combination of client affinity with an unfenced federation wrapper and interrupts database availability.

The record

CVE
CVE-2023-27555
Published
Apr 28, 2023
Updated
Feb 13, 2025
Vendor
IBM
Product
IBM Db2 for Linux, UNIX, and Windows
Classifications
T1499.004
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 28, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 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=11.5

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

IBM · IBM Db2 for Linux, UNIX, and Windowsversion=11.5

Published CVSS scores

5.1IBMCVSS:3.0/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
5.1IBM CNACVSS:3.1/AV:L/AC:H/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.

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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)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Endpoint Denial of Service: Application 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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