CVE-2026-8858: WebSphere Application Server Remote Code Execution

Published Jun 22, 2026
·
Updated

IBM WebSphere Application Server and IBM WebSphere Application Server Liberty are vulnerable to remote code execution and denial of service in the WebSphere Web Server Plug-in component. This vulnerability can be exploited when an attacker impersonates the application server and sends crafted responses to the plug-in.

Affected Software

6 affected componentsFixes available
All of the following
IBM i>=7.3<=7.6
IBM i
IBM Business Automation Insights<=24.0.0
IBM Business Automation Insights<=24.0.1
IBM Business Automation Insights<=25.0.0
IBM Business Automation Insights<=26.0.0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade IBM WebSphere Web Server Plug-ins for IBM WebSphere Application Server to a version that resolves this vulnerability.

    Fixed in 8.5.5.30
  2. Upgrade

    Upgrade IBM WebSphere Web Server Plug-ins for IBM WebSphere Application Server to a version that resolves this vulnerability.

    Fixed in 9.0.5.28
  3. Upgrade

    Upgrade IBM WebSphere Web Server Plug-ins for IBM WebSphere Application Server to a version that resolves this vulnerability.

    Patch PH71376

Event History

Jun 22, 2026
CVE Published
via MITRE·02:16 PM
Data Sourced
via MITRE·02:16 PM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·04:16 PM
DescriptionSeverityWeaknessAffected Software
Aug 5, 2026
Data Sourced
via IBM·12:00 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2026-8858?

CVE-2026-8858 has a severity rating of high at 8.8.

2

How can CVE-2026-8858 be exploited?

CVE-2026-8858 can be exploited through remote code execution, denial of service, and HTTP request smuggling.

3

What systems are affected by CVE-2026-8858?

CVE-2026-8858 affects IBM WebSphere Application Server and IBM WebSphere Application Server Liberty.

4

What actions should be taken to mitigate CVE-2026-8858?

To mitigate CVE-2026-8858, it is essential to apply the latest updates and security patches from IBM.

5

What type of vulnerability is CVE-2026-8858 classified as?

CVE-2026-8858 is classified as a code injection vulnerability.

Company

Resources

Contact

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